Alright, this is really frustrating. Basically, my map consists of a LOT of glass brushes and free-standing stuff. Pretty much everything (with the exception of the actual walls, of course) is a func_detail. All the pillars, short 128 high walls, everything that's not sealing the void. This problem persists, though, no matter what I try. I have two prop_dynamic dropper models, both render incorrectly when looked at through the glass. The glass in the droppers seem to pop through the glass that the player seems them through. I've tried pretty much every visleaf separation possible in the map. I'm out of ideas.

https://www.dropbox.com/s/enhfd2mp4qrj5df/Screenie.JPG?dl=0

Try sending the dropper model an input of "AlternativeSorting 1".