I just wanted to report back that Gravity Forms support will not look at this issue because they feel that since the form works outside the popup that it is an issue with the popups plugin. They suggested that I choose a different popup plugin that is known to work with Gravity Forms, but I really don’t want to do that. I will attempt to debug this issue myself and see what I can find out, but from what I’ve looked at so far it’s kind of a hairy mess between all of the ajax interaction and other javascript.
Thanks for your help though.