No, that shouldn't happen, in my opinion. You don't always know the quality of character of the people you're playing with. You shouldn't be forced to keep Random Person if he/she starts ranting and raving at others, saying awful things, goes afk for the entire Fractal, tries to troll the run, etc. And the rest of the group shouldn't have to completely reset their progress just because Random Person was a jerk and got kicked.