You have told your friend what you think and he rejected it. What is your plan, to kidnap him, tie him up, and beat him until he gives up his delusion? Or do you just hope to browbeat him until your friendship is irrevocably damaged? It sounds like you have done your due diligence already.

Didn’t Mark Taylor say that God told him the Republicans would hold the house earlier this month? If so, then he can’t be a true prophet because what he foretold did not come to pass (jer 28). Point this out to your friend.