I used Mac for The Malfunction yesterday, even with the Venom Resistance nerf he is still a strong character, and I was getting his barrier back very quickly, with his barrier lasting a long time (I’d love to see how long it would last with Barrier Battery).
Lahni is still a strong character, you just have to be a tad more calculated when you go to melee enemies.
I did The Malfunction with a full Scorpio squad and they are still very strong, its just that the other options now are very strong, Kait, Fahz, Cole, Lizzie, JD and Emile are all viable characters in Escape.