I think this is the wrong take. I think this is more about the other person's ego, not OP. There are many ways to move things forward, it's not like this potential person has some key to the kingdom that other potential partners dont.
When a company is just a CEO and a CTO, someone in the c-suite has to take the garbage to the dumpster.
I don’t have a side, but one of them is working for free on a company they don’t own…because if they did own some of it, the titles would be settled on the corporate documents.