I'm finding the same problem with the accursed wind shelters.
These missions seem IMPOSSIBLE most of the time.
The game does numerous things during one of these:
1. Creates about 4 outdoor "rooms" with a boss or two in each.
2. Buffs the bosses to the point that attacking them is pretty futile
3. Creates the landscape in such a way that you're GOING to get stuck on things if you try to dash by. One of those things is likely to be the boss itself. And running by really seems the only viable tactic here......
4. Spawns way too many overpowered normal monsters.
5. KEEPS SPAWNING THOSE GODDAMN SHADOW BATS. I kept leaving the mission and restarted if the first section had those. My usual tactic of, you know, FIGHTING them, doesnt work during these missions, because they're too fast and wont take hardly any damage, while other enemies build up and spam the area with bullets. Running by them, at least when I did it, was entirely based on luck.
Normally, I love games with high difficulty. Currently I generally play this game on Hero difficulty, and I'll likely up it later on once Im more familiar with everything. THIS mission type..... well, there's a trope on TVTropes called "Fake Difficulty", and honestly, that's what these feel like. No other mission type has this problem (even if they can be bloody irritating sometimes). JUST this one.
The only way I found to get through this was to just keep hurling new characters at it and storm dash my way through...... after setting the difficulty to "featherweight" so that the slightest mistake wouldnt instantly eat their healthbar. I really hate having to do that to pass one of these, but nothing else whatsoever was working.