OK so.....

Lets go back to the cup/cone/spindle BB and try a few things. Starting with the fixed cup...

1. Measure the depth of the threads on the cup and compare to the depth of the threads in the frame. To me it doesn't look like the frames threads are cut overly deep. Is there a chance the cups bottoming out?

2. If the thread depth measures out OK. Thread the fixed cup in by hand. There appears to be a lot of crud in the threads. Clean frame threads with a tooth brush and retry threading in the cup. A tick of effort to thread the cup is OK but just a tick.

3. Move on to the adjustable side and repeat.

4. After fully seating the fixed cup the adjusting cup should only sit out distance equal to the width of the lock ring... OK, maybe 1 extra thread is ok. Anything more than that means either the spindle is too long, the cups are too thick or both.