Given the US, talking to a lawyer first is pretty much invariably the smarter thing to do. Even without going this far, you can make statements that then negatively impact your bargaining position later on.

The "truth" is only what can be proved in court. Lots of folks have been tripped up by that before... so be careful.

In this specific case the legal is likely very low. It's a startup and it's unlikely they have money to fund a lawsuit. Plus there's that whole "he's from another country" bit which would make collecting on a judgment pretty damn hard.