In my experience when a glitch loss occurs before the game begins , so if i just get a red screen or you get matched and then get kicked to main screen in the set up phase , then my rating will stay exactly the same . But after i play the next game the points lost to that glitch are than deducted.
One i recall distinctly from a couple of years ago went like this..
My Rating was 484 .
Matched vs a player in the 200s , so knew i would get 5pts if i won or lose 20 if i lost.
Can't recall exactly what the error was , but the game never began and so i requested a match again.
Matched vs a player in the 300s and so i would get 10pts if i won or lose 15.
My rating was clearly still showing as 484 before the game began.
I win the game and at the victory screen it says -10 your new rating is 474.
So i got the 10pts for winning but now the 20pts from 'losing' the previous match is factored in a game late.
Of course if i had lost the 2nd match it would have said -30 your new rating is 454.