I haven't been doing any German hangs. I am not purposely internally rotating in any exercise; I'm just doing the stretch.
I was doing the back lever with palms down, but since switching to palms up, the back lever has felt much better.
I think the issue may be more of a shoulder extension (shoulder articulated down and back like German hang) ROM issue than an internal rotation issue. Maybe it was both though. I'd like to someday do Bulgarian dips, so I might as well work on both shoulder extension and internal rotation.
I'll probably have a lot more time to stretch my upper body now that I've reinjured my lower body. I guess it's a blessing in disguise, since the last time I injured it, I started doing more gymnastics exercises for the upper body.
Thanks for the suggestions, Dr. G. I'll have to be more conscious of my shoulder rotation during exercises.