Dropping into this thread because I have a similar sound after having a CV disconnect after improper torquing after doing solid subframe + poly diff mounts.
I live just north of LAX and I'd be down to have a diagnosing session with you. I repacked the joint, checked torque, marked everything with paint pens (no rotation so far), and a few other things. DM me your number if you'd like.
next step is to chock up the front wheels, raise the whole rear, and spin the wheels and see if I can isolate the sound that way.
meanwhile I've been debating which CV to go with if it's that. Junkyard pull (rarely fails unless drag racing or drifting) or
this one. Someone on reddit has been running one with a welded diff without issues. Still feels stupid to cheap out on an annoying job to risk it failing eventually.