What should the paperwork say and should it be from all three people who’s on the paper as the company or is just from him good enough?

I invested $20,000 in a company that my friend started (we aren't really friends anymore). He gave me a promissory note that he signed. I signed nothing. He's gone back on a lot of the things he said including the amount I would get back. I trusted him that what the note said was right and it wasn't. Now he possibly has a big investor and to finish the deal he needs my boyfriend (who came up with the name of the company) to sign over the mark. I have a little bit of ability because of that to get the right paperwork so when they get a larger investor I am paid back first.