You theory is plausible, but there is no need to explain the lack of public information. It's entirely reasonable that the investigators doesn't feel they require the inputs of thousands of amateurs and thus publicizing every shred of evidence they come across just isn't a priority(1).

Specifically addressing public background checks on all passengers: These are people whose families are grieving. The have a completely reasonable expectation of privacy, and I don't think there is good reason to ever publish any but the most rudimentary of information on these individuals.

Can you imagine a loved one dying in mysterious conditions and then have Reddit shred through their background information and publishing conspiracy theories about a link between their experimenting with drugs in college, a painful divorce and how that means they might be a suicide-hijacker (or whatever)?

1: I'm not saying there's no value in it, there are clearly some capable people pitching in left and right, but it's a radical paradigm shift in investigation, and while you're looking for a missing aircraft is a time for sticking to procedure, not undertaking paradigm shifts.