So it appears that you can lock yourself out of new characters. I was trying to unlock Tote (the frog) but she was whupping my ass due to hazard spam so i decided to reset by exiting to menu, but once i reloaded my game and defeated the wizard boss again her encounter didn't pop up on my map. I then did another dungeon run but she still wouldn't appear on the map.

I don't think that unlock character events are guaranteed. My personal experience with Pochette is that I had the first two encounters early on, but the third encounter manifested many dives later. By that time, I'd already unlocked Satchel and Tote, and was gathering parts of Cr8. So it might just be unfortunate RNG.

It wasn't just rng I ran multiple saves looking for her but she only spawned after i uninstalled and reinstalled the game, and to add to the ever growing list of bugs it appears that after I lost to the king my village was completely reset.