I've got no help for you. Just wanted to comment that there seem to be a rash of stuck BB threads during the last week or so.
Wonder what's up with that? Planet's not aligned right? Moon wobble? Maybe COVID can do more than we think!
As usual, consider letting one of your LBS's take a shot at it. If their mechanic has been wrenching for a while, then they probably have dealt with stuck BB's enough times to know what works for them. Maybe even down to the point of knowing what works best for that specific type BB in that specific shell and the material the shell is made of.
Last edited by Iride01; 07-20-21 at 01:31 PM.