I have been running Hidden shrine of Tamochan at my local game store, with another DM running an additional Hidden shrine game in the same slot. We allowed the players to have the benefits of a short rest, however, they also incurred poison damage. We ruled that they are unable to take a long rest until they escaped the gas, they have not escaped the gas in 3 sessions. The parties are both mainly experienced players, and reasonably well equipped, all of the them running Forge of Fury prior to this adventure. My party is about 2 rooms from escaping the gas, the other party is 1 room away. The gas played nicely I felt. The damage was not a lot, but it adds up, and that coupled with some possibly difficult combat encounters, really depleted a lot of slots, forcing the parties to move through the gas, instead of searching every room very thoroughly. Both parties really enjoyed the Palote Game.