Oh, I was thinking that you needed the simulator in order to reproduce the bug. If I understand correctly now, you are talking about 2 different things: on one side Apple rejected your build (which can be due to several causes), and on the orher side you want to use the simulator to take screenshots, is it right?
I'll check this evening if the framework I'm using is valid for the simulator, I never use it. If so, you'll need a local builder in order to work with it.