Olivia Clark didn't see any problem with her situation.
Letting Yvonne Finley speak openly would simply help her solve a problem, wouldn't it?
Would Mrs. Baker really have a reason to blame her?
Yvonne Finley and Jake Baker are seemingly on bad terms. Jake constantly insists that he's pursuing Yvonne, but she never refuses his advances. She even engaged in scandalous conduct with someone else at school, a clear betrayal of the teacher's code of conduct and stain on Cambria's reputation!
The key point is...
Their intimate in-school attachment can only mean they are a teacher and student.
If she was a teacher...
Most male teachers in the school are well experienced in their career, aged around forty or fifty. Even the young ones are in their late thirties. Basically, all of them are established men, some even older than sixty.
If she was with one of them...
Then Yvonne Finley would be seen as a homewrecker, deserving people's disdain. She would be seen as even more despicable!
