The transaction one is pretty straightforward as written I thought:
Make a post in the submission thread, and @ the other person.
They "Like" that post
That's all there is to it.
As for misprints, I'll note that the same questions could be asked of basically any tile to do with collecting games. Seriesous for instance, if you don't already have a completed set you'll probably have a bit of trouble completing that tile within the week, especially with COVID happening. It's one of the tough things about balancing this sort of event; I want it to be not TOO easy, and collecting is a tough pillar to give tasks for without being unreasonable (e.g. "Own Stadium Events"). A misprint is something that CAN be had incredibly cheap (e.g. Gundum Battle Assault on PS1).
I'll be nice and say that your amiibos count, in this instance.