I think they were likely socially rejected by Tarshis. Jk clearly expected to play golf with him. When he found out Tarshis was asking after his plans, it was either to be polite, or so he could avoid him, but not so he could socialize with him, he’s now a liar and moron.
And you wonder why no one wants to have anything to do with these social rejects. Their inappropriate behavior at that dinner what, a year ago? Was witnessed by several people. Tarshis has probably had to explain it socially and now legally. Imagine trying to ingratiate yourself with Barisones lawyer. People notice these things.
He was never going to play golf with you. If he actually said he would, it was to be polite in the moment and save himself the embarrasment of actually saying no. A bully might not get the subtleties of not being wanted, though.