No, it wasn't annoying, just weird. Yes, the Inner Parasite battle happened. It would be lovely, but useless, since I'm in the endgame save room. If you want, I could send you the save file.
Viewing post in Weird and Unfortunate Things are Happening comments
Thanks, but I don't think that'd help. I know what switch needs to be on for Miriam to learn skills, I'm just not sure how this happened, as I haven't been able to replicate it.
The only way I can think of is if you killed the Parasite before turn 4, when Miriam is supposed to return and help (which is also when her skill-learning unlocks) but that's supposed to be impossible, as all attacks are supposed to just do 1 damage to it.
All I can do at this point is apologize and set in countermeasures to make sure this doesn't happen to anyone else. I'll make sure that the start of the new content in the final build checks to make sure Miriam can learn skills as well, so you should be able to still use your save. Sorry that I don't have a better answer, but thank you very much for reporting this.