Soft brick update custom rom to stock 6.0.1

[ezas]

I have a SM-G900V that was on a custom 4.4.4 ROM. I'm selling the phone and wanted to give a stock but updated phone to the guy.

I downloaded the latest for 6.0.1 for the Verzion G900V and flashed it in Odin. It got a write fail. I tried again and it went further but then got another write fail.

Now when I try to boot the phone it goes to Software update failed error. I can boot again by long holding the power button. The phone is still recognized in Odin.

The bootloader was unlocked
The emmc was 15.
The build number of the custom ROM was: Build: KTU84P- G900VRU1ANI2

I'll keep searching for a solution but the guy I'm selling the phone to is freaking out so any and all help would be much appreciated.

 

[ezas]

update

I tried flashing the same build as what was on the phone AN12 and it failed with an Auth fail error in Odin. I did some research and saw that could be a CSC problem. I tried using Kies because I read you can find the CSC code that way. I couldn't get Kies to 'talk' to the phone. It saw that a phone was connected but it wouldn't created the connection. I tried firmware recovery but I need the serial number and Samsung in its infinite wisdom doesn't put the serial number on the sticker inside the phone (at least it doesn't on US Verizon).

It's a phone from Verizon (originally bought on contract) in the US and I have been using US Verizon downloads from either updato or sammobile (for the 4.4.4)

I could realy use some help. I'd like not to bork the phone by just trying hail mary solutions.