So if the dates don't match up, this could 100% be that Peetz went and got tested after Chantal to make sure he was ok.
That said, from personal experience, I know 4 people that got false negatives for COVID while they showed symptoms and tested positive later (2-4 days). I don't know the reason why false negs happen...maybe the nurse or whatever didn't put the swab far enough back or maybe there's some other science behind it.
In the end though, it doesn't matter. It's way funnier for her NOT to have COVID. Because she was claiming to have problems breathing and all the other shit....and for what? Not Covid? She seems to have completely glossed over the fact that 1) she doesn't have covid and 2) she claims the doctors said she was healthy (but they were glad she came in).... so she's not at all worried that her healthy self was having such extreme health issues?