Yes, the implication is that the school wanted her out so she'd stop bothering them, and that the school allowed her "internship" at a vaudeville theatre mainly because it was very, very far away. She never reported to Goliath or to the owner of the theatre. She seldom did any kind of schoolwork. Consider it an honors course in not bothering the teachers.
It was mutually decided that the best place for her to be was "away", and her options were limited. Sofia would never admit to it, and nobody else would call her on it, though.
Jason Crest is a band that I was listening to at the time. There's nobody by that name in it; it was named after one of their songs, "Justin Crest", which wasn't even on their album. This was based on Napoleon who, it was said, knew everybody in his army. I think this is one of those traits that I tossed in because I might be able to do something with, but couldn't, given the setting. She knows who Brisbane's ancestors are. Caleb's heritage is a total mystery.
When I started writing the comic, I came up with about nine pages of random one-shot jokes. This was one of them, and I needed to fill out a week. This was more of an anti-joke than anything else. I think Charles Schulz could've pulled it off with Snoopy and Woodstock. It's less funny with my characters, and I have no idea why.
Yes, all of Brisbane's knock-knock jokes involve St. Francis Xavier; I think I wrote this one first and tossed it into the random gag pile. It inspired a comic in the new intro. I should've just left it at that, because the idea of a joke that bad is funnier than the joke itself.
Meanwhile in France...pt 2 drawn by Lien Nguyen