I'm trying to do Render Unto Ceaser, but every time I try to go to Cottonwood Cove, the legion turns hostile. I have the mark of Ceaser, I'm not wearing any faction armor, and my followers aren't with me. I tried using console commands to set my reputation to idolized, but they still attack me.

A good idea might be to equip a pair of NCR armor and then take it off again.

I've never run into this problem before, but I'm guessing that the game is assuming that you aren't actually "idolized" with the Legion.