From what I understand, the
criticism is that Fire Burst Traps are "useless" or "too weak" because the Heroes can just run out of the room to avoid damage when they find one. I'm not sure that is always going to be the case (a Fire Burst can either be in the room based on the quest map, but also discovered by searching for Treasure... 2 cards in the deck are added by WOM).
Some speculated that the original "difficulty" was because the EU 1st edition didn't allow backtracking (so if there isn't another way out of the room you risk being hit... and you typically will only have one chance to neutralize it with a spell), but that the EU 2nd edition allows backtracking, hence a Hero could just move easily out of the room to avoid it.
I haven't played these quests yet so I can't say really whether it is super easy or not. I don't deny that there are errors in official quests, and it can be a bit overwhelming to catalog them all, but if you're Zargon, you can do research beforehand to find what they are so you're not caught off guard. Most people say WOM is very difficult, but maybe not because of the Fire Burst Trap. So if this particular Trap is "easy" maybe that's forgivable if the rest of it is so difficult.
Apart from that, some Empty chests and some vagueness over how to handle interactions with Pits of Darkness (the same icon is used from the Against the Ogre Horde which first introduced this new trap, but no explanation is given IN WOM, so it's Zargon's option whether he just treats them as normal pits or as they were probably intended, as this new type of trap) seem to be what people have found.
If you think the difficulty will be frustrating and kill the enthusiasm of your players, I would give them some more opportunities in the form of allowing them to hire mercenaries (already a feature of the pack), and maybe give them some more potions (if playing under NA rules they will be visiting the Alchemist Shop(s) anyway just like visiting the Armory) between quests.