How rigorous will VCs be at analyzing the citations around my TAM calculation? (I will not promote)

I'm trying to calculate the TAM for my VC pitch deck but the problem is I can't really find a primary source for the stats I'm trying to use. In my situation I need to know the number of *active* TikTok and Youtube channels that have like > 5k followers. The problem is I can only get weird stats not from a decent source like "Acme says TikTok has 1M active creators" but that's not on Acme's website nor can I find where that was originally mentioned I even paid for Deep Research to see if it could find better source than I could and it didn't come up with any. I think what I'm going to do is to PAY for a social media monitoring platform to give me decent numbers.