How the fuck do I deal with them? I can't kill one as a rogue on my own. They drain all my wisdom at MOST with two hits since I have 10 WIS, and they frequently crit.
What the fuck am I missing here?
First, this is an example of terrible encounter design, straight up. It basically requires either specific foreknowledge and explicit group optimization for the encounter, lots of save loading, or lots of cheesing to pass.
Second, though, given the above, I think this might legitimately be intended to force the players to utilize the difficulty sliders in the options, if that's intended to be required for encounters further on. I found that by cranking every difficulty setting possible down to the lowest level (make sure you do enemy damage last, at it resets with some of the other dropdowns), it becomes barely passable, even with my pure ranged support bard having volunteered her name without giving me a choice. Also make sure you remember your previous settings to reset afterwards (as desired).
I strongly suggest you pretend this encounter is intended to be passed only using the in-game difficulty options, like some meta Metal Gear style puzzle, because that's easily the most generously favorable interpretation of the encounter design.