> They reached out to me wanting a "Consent and Coexistence Agreement", I told them not for free, to which they never responded with an offer.

Man, imagine if you had asked for a thousand euros as consideration.

So, you would spend several thousands of dollars to register a trademark to protect it from other corporations, and then the first thing you would do is give out the right to said corporation for 1000 bucks? I'm not an expert, but that sounds like a bad deal to me and substantially weakens the mark.