"I am guessing that he is pissed that he tried to "play nice" and sound concerned and I was business-like with him back."
Great insight. Too bad for him. He isn't the good guy and it isn't you job to make him feel like he is.
"I'm not rising to the bait. I'm not even answering him until tomorrow afternoon, the earliest."
Yay Donna!!!!!!!!
"I really don't want him in the yard; IC doesn't think he should be there, either. I'm debating about what I might respond to with that. "
Hmmm... How about, "I don't want you in the yard. I'll deal with the upkeep. Thanks for the offer, but no."
After all, this says it all: "I really don't want him in the yard."
All the rest about his role, blah blah blah, is co-dependent/managing him stuff. Not you job to create conditions in which he can act out his preferred role.
