This is fixed. GEMS 22.214.171.124 will be out shortly. I went with the solution of changing the "Next Card" placement behaviour. It now resets the layout cursor to the front first column of the current card if its empty. I think that is sane, but I have not really thought through all the edge conditions. Let me know if it causes trouble. I am mostly bothered because I know common nonpartisan second cards has worked in the past, and that changing the next card behavior was not the solution. Seems the correct answer to me today though.
Note that GEMS 1.16.2 will break download to AVTS 3.12.x. I got sidetracked by this problem and a couple of other things today, so the matching AVTS 3.13.1 won't be out until at least tomorrow.