How long did you have to wait before Polly showed up at the keyhole? I've checked two different walkthroughs to make sure I didn't miss anything in the Fetch Rock exhibit, and I even rang the bell on the wall a couple times (which apparently you don't have to do?), and she's not appearing. At first I thought it might be a QuickTime issue — maybe it's trying (and failing) to load a video — but the intro and other videos work fine. Anyone else have this problem, and if so, did you fix it?

EDIT:
After perusing one of the walkthroughs further on, it says you can't find the EMP goggles until after you've met Polly and gotten the location, which is not the case: I found the goggles long before I found any evidence of her presence, let alone talked to her (which, obviously, I could not do). This sounds like an out-of-sequence bug that's keeping me from going any further. Can anyone else confirm this? At any rate, I'll have to start the game over.

EDIT #2:
One other note: since the save files are plain-text and easily editable, I changed the goggles flag to "off" and tried again. The goggles were indeed no longer in my inventory (I found them back in the radio tent but didn't touch them), but Polly refused to show up. So, if I could change the topic to report this as a bug, I would.