If 1 research meant fail, 75-80% of this board would fail because it doesn't seem like many people had multiple research.
Historically the pass rates of members on this site seem very high, so I don't think the number of research makes a huge difference. If people are willing to dedicate time to chat about the exam with strangers they are probably dedicated to studying as well. That's my guess why it seems like most people on this site seem to end up passing.
I think the 2 research makes sense because you're getting full points those as opposed to a sim that has multiple parts and thus a higher chance of not getting full points. However, I don't think getting 2 has anything to do with how you did on MC or is necessarily an indication of passing…maybe just increases the odds in your favor.