I don't know what the fuck you just said, but no, the fact that we're debating the meaning of "hook up" only proves that there's no conclusive proof that sex occurred when they were drunk. There's no debate over the meaning of "swapped spit" because that's a very clear slang term with a singular meaning, which is making out and NOT sex. Ambiguity with A does not necessarily result in ambiguity with B just because A and B are tangentially related. In fact, it would make perfect sense if in BOTH cases they merely made out, maybe a bit of heavy petting at most, and Michelle just has unusual values about what those levels of physical intimacy mean for a relationship.