Does TMM only launch one game at a time?

I'm sitting in the TMM queue for 2v2s. 12 people in the queue. 5 seconds left to match. ~6 seconds later, 8 people still in the queue.

Does the game only launch 1 game with 4 people? Can it not launch 3 games at once with 12?

The matchmaker has a game quality threshold so it will no launch a game if the quality is bad

That doesn't really answer the question. I've been on TMM all night and this sort of thing like in the OP happened quite a bit.

TMM frequently launches multiple games at once if there are sufficient players that can be combined into games of sufficient quality.

It just means that the group of players doesn't have many good possible matches

Does TMM only launch one game at a time?

No.