A few more calls....
Now I have spoken with Ultra Cycles, and I got a different impression from what some of the others have gotten. I heard the part about their lawyers checking into the shell activity, BUT it is primarily because the name Ultra Motorcycles is involved. I also got the distinct feeling that the people talking to us on the phone don't know the whole story, because I could ask a very pointed question and get one answer, then ask the same one in a different way and get something different.
So, I don't know that the answers I got are 100% correct, but she did say that even though they may want the shell back, it does appear to legally belong to the other party. FWIW.
Mama and Daddy always said it's how you play the game - trade to trade well and the rest will fall into place ;-)