It's been pointed out, but the Republican Senators didn't say they talked to him. They specifically said they spoke to him. Talked implies a two way conversation. Spoke can be two way. It can also be one way like I spoke at a conference or I spoke to the ghosts in my house telling them to leave.
So technically the Senators could have had someone put Mitch's phone up to his ear, spoken about whatever they wanted, and all the while he was a vegetable and braindead and those Senators wouldn't have been lying about having spoken to him.