Unless I'm misunderstanding, the OP wants to re-enter the park? If that is the case, he/she may not be ablet to get Fastpasses for the entire party without all being there.
In the summer, we were hanging out at Polynesian, before Kona Cafe ADR, so hubby ran over to MK on the monorail. He entered MK, and all was good when he did his FP, but when he did mine and kids, no go. The computer knew that we had not entered the park, so it would not give him a FP. He was able to get a supervisor CM to override the system, as this part of the equation, just slipped our minds, and so we got our FPs. Kids and I started into the restaurant without him, and he then relayed the story, and we both said, "Duh!"
Just wanted to alert you to this. I think you should be ok, as the party will have already entered the park. But this whole scenario has me gently remind people, that once in awhile, there may be glitches like this, and it costs time when this sort of thing happens.
Good luck in getting your passes, Tiger