CHAPTER 12 and 13 SPOILERS
Suggestion: it seems if Camran breaks up with Vess on Erigone, he's unwilling to allow her to return to the crew, even if the break-up is the only negative response he ever chooses.
But these two things are not necessarily related, let alone that closely. I think he should at least have the option to adhere to Eva's objection regarding Vess' fate.
In this particular playthrough I had Camran show interest in Vess, then discover he was actually in love with someone else (who wasn't an option until that point in the story) and break up with Vess at the next opportunity. So in that case the betrayal was more of a convenient excuse than the reason for the break-up.
While that's kind of an edge case it brought to my attention that even if the betrayal is enough reason to break-up, it's not necessarily enough reason to condemn Vess completely.