It is illegal to give false or misleading statements in order to defraud other investors, but it isn't illegal to "talk your book" if you aren't outright lying about what you are saying. You can flip on CNBC and expect to see lots of hedge fund managers hyping up their positions. That's not fraud.

If you are saying there is some fraudulent behavior involved in one investor calling another investor to fact check a founder's claim, I'm still not seeing it.