Quote: "does anyone here have any advice?"
Not trying to sound like a wise guy, and you did ask if
anyone has
any advice, so please do not get mad at me for sating this, but...
If that version of Pi is not supported and unknown when it will have support, then you may want to simply use a version that is supported.
I meant to explore the Rasberry Pi aspects of AppGameKit but never got around to getting a board to play with it, so sorry if I am not being much help.
But for me, if I were in your position (from the way it sounds) , I would not abandon my projects or AppGameKit, but would rather step back a board until the functionality does get there.
Just because they are too busy now with other things is not the same as them saying it will not happen, so it may be on the way at some point.
Probably lots to do with the other boards until then, and that work should be portable to the 4 right?
Coding things my way since 1981 -- Currently using AppGameKit V2 Tier 1