What makes a DragFly4 not spin besides PCB, stiction, or FDB

[ThomasH]

I have a 1.5TB DragFly4 WD15EADS-11R6B1 that doesn't spin. It sounds like it tries for just a light tick but does nothing.
ClientPCB spins Donor HDA, with and without extROM transplant.
DonorPCB behaves the same as Client PCB on Client HDA: No spin.

Heads aren't stuck.
Platters/Motor aren't stuck, and I don't see any obvious damage. I don't open a lot of these so don't know how tight is normal, but it seemed to spin freely, unless too much juice was needed to get it going? I think it's normal though.

It has been to another lab first, but wasn't opened. The ClientPCB looks a little mangled at the connections but has been bent back and straightened out, and does work on the DonorHDA with DonorROM transplant.

Update: changed ROM headmap from 'From Map' to "Default" and it now spins up and clicks, then spins down...like bad heads.

This normal for these?

[Balvan]

Bad heads / media damage can cause this.