Some resolution: for others with same issue!
I am doing some guessing here but I made some discoveries along the way. This is just related to the question bank problems per original title.
1) Errors do not necessarily mean failed restore. I was finally able to restore all my courses despite hundreds of errors (yes, I mean hundreds!) related to questions. Patience is the key here.
2) Turning on debugging seemed to allow the course restore to complete. My theory here is that because the system was busy writing the errors to the screen, it did not timeout during this process and allowed the course to continue through the process. If I turned debugging off, the course restore would just stall out (I think, at least the browser spinning circle for loading vanished and nothing happened for a very long time), I would have to delete the course restoration in progress and start again with debugging turned on.
3) Make sure you have something else to do while trying this. On average, my courses with quizzes took one to one and a half hours each to restore. Trying to cut them down to just one quiz did not help the process.
Fortunately, at the end of three very long and frustrating days, all my courses did restore and seem functional. Quizzes seem to be behaving as expected and I am almost hopeful at this time that I can now go and do something else!