Is there any PROOF of "drama" between Reagan and Brett?

I can't find convincing evidence of anything actually happening. How do you know Brett didn't just leave DW due to a breakdown in contract negotiations? These contracts are often renegotiated in December, which would match up with Brett leaving. Maybe Brett asked for more money, DW said no, Brett walked, and DW simply replaced Brett with Reagan because it was the most convenient thing to do. And perhaps none of them want to talk about it due to NDAs (non-disclosure agreements which means they can be fired/sued if they talk). Am I missing some obvious proof that these two women actually had a falling out?