So the dozen or so times I sold short stocks posted to my account that I didn't really own because the trades were later broken shouldn't have happened?
I'll give you 1/2 the money you can recover if you can convince the broker you are right.
I stopped counting at 67 broken, busted and reported in error trades
I tend to believe you sold phantom shares IMO. Heck, even my 2M I bought Monday were phantom shares IMO. I have no doubt the 3B due bills I was owed were phantom shares. Still, I could trade the 2M and AT was on the hook unconditionally.