Pre flash validation failed for gpt moto nexus 6

Trying to flash my Nexus 6 back to Lollipop fm M, but getting problems. I'm posting the output from all three steps below. Any help is greatly appreciated.

+++++++++++++++++++++++ Try flash-all; fails on bootloader issue ++++++++++++++++++++++++++++++
C:\Users\winlee\Desktop\adb-tools\shamu-lrx21o>flash-all
target reported max download size of 536870912 bytes
sending 'bootloader' (3807 KB)...
OKAY [ 0.128s]
writing 'bootloader'...
(bootloader) Motoboot: Preflash validation for aboot
(bootloader) Preflash validation failed
FAILED (remote failure)
finished. total time: 0.320s
rebooting into bootloader...
OKAY [ 0.002s]
finished. total time: 0.002s
target reported max download size of 536870912 bytes
sending 'radio' (67170 KB)...
OKAY [ 2.260s]
writing 'radio'...
(bootloader) flashing modem ...
(bootloader) flashing mdm1m9kefs1 ...
(bootloader) flashing mdm1m9kefs2 ...
(bootloader) flashing mdm1m9kefs3 ...
(bootloader) flashing versions ...
OKAY [ 0.941s]
finished. total time: 3.202s
rebooting into bootloader...
OKAY [ 0.002s]
finished. total time: 0.003s
target reported max download size of 536870912 bytes
archive does not contain 'boot.sig'
archive does not contain 'recovery.sig'
archive does not contain 'system.sig'
archive does not contain 'vendor.img'
Creating filesystem with parameters:
Size: 28474998784
Block size: 4096
Blocks per group: 32768
Inodes per group: 8160
Inode size: 256
Journal blocks: 32768
Label:
Blocks: 6951904
Block groups: 213
Reserved block group size: 1024
Created filesystem with 11/1738080 inodes and 153124/6951904 blocks
Creating filesystem with parameters:
Size: 268435456
Block size: 4096
Blocks per group: 32768
Inodes per group: 8192
Inode size: 256
Journal blocks: 1024
Label:
Blocks: 65536
Block groups: 2
Reserved block group size: 15
Created filesystem with 11/16384 inodes and 2089/65536 blocks
--------------------------------------------
Bootloader Version...: moto-apq8084-71.15
Baseband Version.....: D4.0-9625-02.55.03a
Serial Number........: ZX1G22MHRK
--------------------------------------------
checking product...
OKAY [ 0.002s]
checking version-bootloader...
FAILED

Device version-bootloader is 'moto-apq8084-71.15'.
Update requires 'moto-apq8084-71.05'.

finished. total time: 0.116s
Press any key to exit...
++++++++++++++++++++++++ Try to flash bootloader, also fails +++++++++++++++++++++++++++++++++
C:\Users\winlee\Desktop\adb-tools\shamu-lrx21o>fastboot flash bootloader bootloader-shamu-moto-apq8084-71.05.img
target reported max download size of 536870912 bytes
sending 'bootloader' (3807 KB)...
OKAY [ 0.134s]
writing 'bootloader'...
(bootloader) Motoboot: Preflash validation for aboot
(bootloader) Preflash validation failed
FAILED (remote failure)
finished. total time: 0.334s
++++++++++++++++++++++++ Env vars show bootloader unlocked +++++++++++++++++++++++++++++++++
C:\Users\winlee>fastboot getvar all
(bootloader) version: 0.5
(bootloader) version-bootloader: moto-apq8084-71.15
(bootloader) product: shamu
(bootloader) board: shamu
(bootloader) secure: yes
(bootloader) hwrev: 0x83A0
(bootloader) radio: 0x6
(bootloader) emmc: 32GB Samsung REV=07 PRV=0B TYPE=57
(bootloader) ram: 3072MB Samsung S8 SDRAM DIE=6Gb
(bootloader) cpu: APQ8084 ES1.1
(bootloader) serialno: ZX1G22MHRK
(bootloader) cid: 0x00DE
(bootloader) channelid: 0x00
(bootloader) uid: 76E5530111000000000000000000
(bootloader) unlocked: yes
(bootloader) securestate: unlocked
(bootloader) iswarrantyvoid: yes
(bootloader) mot_sst: 3
(bootloader) max-download-size: 536870912
(bootloader) reason: Reboot mode set to fastboot
(bootloader) imei: 355499060714529
(bootloader) meid:
(bootloader) date: 03-15-2015
(bootloader) sku: XT1103
(bootloader) iccid:
(bootloader) cust_md5:
(bootloader) max-sparse-size: 268435456
(bootloader) current-time: "Thu Jan 15 3: 6:37 UTC 2015"
(bootloader) ro.build.fingerprint: none
(bootloader) ro.build.version.full: none
(bootloader) ro.build.version.qcom: none
(bootloader) version-baseband: D4.0-9625-02.55.03a
(bootloader) kernel.version: none
(bootloader) sdi.git: git=MBM-NG-V71.15-0-gf291c61
(bootloader) sbl1.git: git=MBM-NG-V71.15-0-g60ea7e6
(bootloader) rpm.git: git=MBM-NG-V71.15-0-g18b261e
(bootloader) tz.git: git=MBM-NG-V71.15-0-ge5920ce
(bootloader) aboot.git: git=MBM-NG-V71.15-0-g96f7faf
(bootloader) partition-type:modem: raw
(bootloader) partition-type:metadata: raw
(bootloader) partition-type:sbl1: raw
(bootloader) partition-type:sdi: raw
(bootloader) partition-type:sec: raw
(bootloader) partition-type:ddr: raw
(bootloader) partition-type:aboot: raw
(bootloader) partition-type:rpm: raw
(bootloader) partition-type:utags: raw
(bootloader) partition-type:tz: raw
(bootloader) partition-type:padA: raw
(bootloader) partition-type:sbl1bak: raw
(bootloader) partition-type:abootBackup: raw
(bootloader) partition-type:rpmBackup: raw
(bootloader) partition-type:utagsBackup: raw
(bootloader) partition-type:tzBackup: raw
(bootloader) partition-type:versions: raw
(bootloader) partition-type:frp: raw
(bootloader) partition-type:mdm1m9kefs1: raw
(bootloader) partition-type:mdm1m9kefs2: raw
(bootloader) partition-type:mdm1m9kefs3: raw
(bootloader) partition-type:padB: raw
(bootloader) partition-type:sp: raw
(bootloader) partition-type:keystore: raw
(bootloader) partition-type:logs: raw
(bootloader) partition-type:persist: raw
(bootloader) partition-type:mdm1hob: raw
(bootloader) partition-type:mdm1dhob: raw
(bootloader) partition-type:cid: raw
(bootloader) partition-type:logo: raw
(bootloader) partition-type:misc: raw
(bootloader) partition-type:padD: raw
(bootloader) partition-type:mdm1m9kefsc: raw
(bootloader) partition-type:ssd: raw
(bootloader) partition-type:recovery: raw
(bootloader) partition-type:kpan: raw
(bootloader) partition-type:boot: raw
(bootloader) partition-type:cache: ext4
(bootloader) partition-type:oem: raw
(bootloader) partition-type:padC: raw
(bootloader) partition-type:system: raw
(bootloader) partition-type:userdata: ext4
(bootloader) partition-size:modem: 0x0000000007000000
(bootloader) partition-size:metadata: 0x0000000001000000
(bootloader) partition-size:sbl1: 0x0000000000060000
(bootloader) partition-size:sdi: 0x000000000000e000
(bootloader) partition-size:sec: 0x0000000000004000
(bootloader) partition-size:ddr: 0x0000000000008000
(bootloader) partition-size:aboot: 0x0000000000100000
(bootloader) partition-size:rpm: 0x0000000000040000
(bootloader) partition-size:utags: 0x0000000000080000
(bootloader) partition-size:tz: 0x000000000007d000
(bootloader) partition-size:padA: 0x000000000040f000
(bootloader) partition-size:sbl1bak: 0x0000000000060000
(bootloader) partition-size:abootBackup: 0x0000000000100000
(bootloader) partition-size:rpmBackup: 0x0000000000040000
(bootloader) partition-size:utagsBackup: 0x0000000000080000
(bootloader) partition-size:tzBackup: 0x000000000007d000
(bootloader) partition-size:versions: 0x0000000000001000
(bootloader) partition-size:frp: 0x0000000000080000
(bootloader) partition-size:mdm1m9kefs1: 0x0000000000100000
(bootloader) partition-size:mdm1m9kefs2: 0x0000000000100000
(bootloader) partition-size:mdm1m9kefs3: 0x0000000000100000
(bootloader) partition-size:padB: 0x0000000000100000
(bootloader) partition-size:sp: 0x0000000001000000
(bootloader) partition-size:keystore: 0x0000000001000000
(bootloader) partition-size:logs: 0x0000000000200000
(bootloader) partition-size:persist: 0x0000000002000000
(bootloader) partition-size:mdm1hob: 0x0000000000040000
(bootloader) partition-size:mdm1dhob: 0x0000000000008000
(bootloader) partition-size:cid: 0x0000000000020000
(bootloader) partition-size:logo: 0x0000000000800000
(bootloader) partition-size:misc: 0x0000000000100000
(bootloader) partition-size:padD: 0x0000000000278000
(bootloader) partition-size:mdm1m9kefsc: 0x0000000000000400
(bootloader) partition-size:ssd: 0x0000000000002000
(bootloader) partition-size:recovery: 0x0000000001004000
(bootloader) partition-size:kpan: 0x00000000008e0000
(bootloader) partition-size:boot: 0x0000000001000000
(bootloader) partition-size:cache: 0x0000000010000000
(bootloader) partition-size:oem: 0x0000000004000000
(bootloader) partition-size:padC: 0x0000000000100000
(bootloader) partition-size:system: 0x0000000080000000
(bootloader) partition-size:userdata: 0x00000006a13e0000
(bootloader) qe:
(bootloader) ro.carrier: unknown
(bootloader) dm-verity-state: Not Supported
all: listed above
finished. total time: 1.394s
++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++

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