I assume he would follow his normal pattern- confront Tibor aggressively and get him to stand down, thus solidifying his control. Or, if Tibor doesn't relent, turn on him as a traitor and lament his betrayal to his remaining supporters, with the tacit expectation that they will do what they can to soothe Evans's bruised ego while finding ways to attack Tibor online.
Evans doesn't have a particularly varied playbook, from the looks of it.