I think it's really hard for Trump to negotiate anything when he has dementia-related speech and mental processing issues. I doubt he could legally sign a US contract. I think that's why he has other people do his work for him.
JunkboxJim"The president is exasperated. I don't think he believed it was going to be this difficult to get the Iranians to agree to a deal." Which is why he thought he didn't have to have a fully thought out strategy with considerations of alternate "what if" scenarios worked out in advance.