I had a "I've got to go AFK for a while" on infected ground the other day, we were already down two and we were right before Ogden, so we had to sit and wait for him for 15 minutes, when he finally came back, we tried the room once and before we could give it another try, he had to AFK again. Then I had another group where everyone claimed they'd done it before, but only two of us knew that you had to activate all three consoles at once on the generators in Simmons' room. Then one of them decided to "test the water" we literally spent an hour and a half in that one room, because we kept having to redo the generators as their timers ran out.