Can I just say, the Janet-only fight is bullshit? The enemy is immune to both blind and poison, making half of her kit unusable, it deals way too much damage for not having a tank character present, and if it happens to proc confusion then you just lose the fight no matter what. I have tried this thing multiple times, and every time I wind up getting confusion and dying with no counterplay.
I think just removing the enemy's ability to inflict confusion would make it okay. It would still be a difficult fight, especially with Janet's best defensive option and most consistent offense option (blind and poison) being unavailable, but it would at least be possible.
I would say that any time a fight is solo, CC effects probably shouldn't be inflicted on the player character because without teammates there's no counterplay. You either are lucky and don't get CCd or you are unlucky and probably die. With teammates you can heal or status cleanse the CCd character as a counterplay, but that's not present in solo fights.