Then the only option is to swap positions so the corn is under the BP since the latter prefers warmer temps anyway. I'll get that done tomorrow and see if the parameters improve. Hopefully that works because otherwise the LAST last resort would be to figure out how to unscrew and reattach one of the RHPs so they're on the same side for both enclosures. Actually tried to do that when I first cleaned the corn's PVC but it's really stuck fast in the ceiling...
As for the off-gassing, it's impossible to tell. I think it's just all the new plastic objects being warmed (not melted, just warmed) and mixing with the moisture from the substrate because the RHP didn't produce any peculiar smell when I tested it at full power for a few days back when the enclosure was empty. At any rate just all the more reason to let it run without an inhabitant for a while yet.