I am in the Mordon maze and just Nor and I wanted to reform the party and leave Ignus in the control room with the other Mordrons and go back and get Nor, but the reform party button is greyed out. Any help?

IIRC, you aren't supposed to be able to reform the party anywhere in the maze; I think Nordom's room and maybe the boss room are an exception.

Since the maze doesn't change until you explicitly reset it, you should technically be able to ask the engineer to teleport you out, leave Ignus wherever you like and go back into the maze to get Nordom. (Save before trying, though; I never keep Ignus past his mage training, so I don't know for sure - and my solution likely would've been to call him "supplicant" a couple of times. :D)