From what I’m seeing, much of this matches up with Mozilla’s political views and none of it is a surprise. Sounds like a “monster of the week” right wing piece.
In that guy's mind the boogeymen are thinks like diversity and (I guess not surprisingly nowadays) "vaccine acceptance". Like, with normal people maybe it would be useful to know if some nonprofit had ties to Nazi/white supremacist orgs or people, but in the modern RW mind having ties to science or diversity advocacy orgs is the same thing from their perspective.
I stopped reading closely about halfway though and skimmed the rest. The author seems to be "just asking questions" rather than actually doing much investigation. It's not new or surprising, for example, that Google's search deal is the bulk of Mozilla's revenue or that a non-profit can own a for-profit subsidiary. That's about where my attention waned, but it seems the author's main beef has more to do with payments to liberal-sounding organizations than any sincere concern about financial shenanigans.