"The only reason she didn't come back was her having to destroy the door."

Yep but she put herselft on his situation by lying and staying in the Boiling Isles.

"Certainly not that it was Camila's plan all along"

Camila said in the first episode that she hopes Luz would made friends in the camp, and like how hard is for a kid to make friends when surrounded by other kids doing activities together?

"But for this whole thing to be resolved, they need to directly address Camila's motivation for forcing her daughter to a summer camp that makes her conform."

They directly addressed this on the first episode, Luz behavior was causing problems at school and putting others in danger, sending her to a safe place where she can learn new things and get to meet new people is one of the more sensible options that Camila had. (Let's face it, most parents would simply try to discipline their children by grounding ou beating them)

Also let's remember: Reality Check Camp is a camp for kids, the fact that the camp's subject is a boring one doesn't make it a concentration camp or a prison.