What happens when a guy gets kicked in a match? Does he receive matchmaking points just like he would normally, is it changed somehow, or is the match treated like he never was there?
It counts as a loss if you get kicked.
Also, be aware that getting kicked to avoid a competitive ban is a load of hogwash. You will still get banned for getting kicked, and worse still, the people who kick you get a black mark against their name for initiating the kick if it occurs too much!
If you get kicked, it counts as a loss for you, regardless of the match outcome. Source
The information is not public. The ranking system is a black box (with the exception that we know it uses a modified glicko-2 algorithm).
There are currently no public or well constructed tests/analysis done to figure the system out.