I disagree. Learning the ins and outs of the law and of IP negotiations - a very specialized and cut-throat field - in a few days or maybe weeks is out of the question.
If he can't talk to a lawyer, he's going to lose. Period. Maybe very badly. After having already screwed up, now is not the time to half-ass it.
You're not a terrible person but you've given absolutely terrible advice.
At what point did I tell OP to become an expert on IP law? Nowhere. My advice to OP was to educate himself so that no matter what he did he could be more effective.
> You're not a terrible person but you've given absolutely terrible advice
You didn't read my advice correctly and I place zero value in your opinion about me being a good person or not especially considering you thought you had enough information to even bring up the topic based on one short internet comment.
Now you're nitpicking. Sure, he can educate himself and should. But in the amount of time he has (can't be much) he can learn basically nothing. It's too late for that path to make any sense.
As for the other thing, looks like you're intentionally picking a fight. Therefore, out of deference to your better logic, I withdraw my comment that you are not a bad person.