There was a leaver but I got stuck in game?

I’m queue in a three stack, there was a leaver in the beginning of the game so it canceled and everyone left EXCEPT ME and I was stuck on the map alone but I couldn’t leave because I would be given a leaver penalty then it finally kicked me and I lost SR

There is currently a widespread DDoS attack that may have caused this issue.

Please avoid attempting to queue for Competitive Play at this time.

Will I be given my SR back?

No. DDoS attacks hit the network providers (and not directly the game server) so it is more or less a disconnection. See this thread for Blizzard’s standing policy about this:

As long as you do not allow yourself to leave any more Competitive Games you should technically recover your SR within a few games (once the issues are resolved) as your hidden MMR and SR will be out of alignment.