Didn't connect to a game because a teammate was unable to connect

Okay, so Firstly I've never had league connection problems. Even when ranked is disabled and loss prevention is given out I always connect with no issues.

So yesterday, I loaded a game. Of the 10 players I was the first to 100% loaded. I waited and waited and 9 players were at 100% while a teammate showed "not connected". After a few minutes I thought "normally even if someone was dc'ed the game would have started by now" so I exited the client and reopened league. I didn't even need to re-enter my password or load the client or anything, literally as soon as I clicked on my desktop shortcut the client opened and said "click here to reconnect", AND it tried to start a new instance of the client (which I closed after the game). I then had to reload the game from 0 to 100%, and when I joined the game the solo lanes were at level 5 (I was adc, my support was still dc'ed and bot Lane hit 4 as I got to Lane).

What's even weirder is MY SUPPORT CONNECTED LESS THAN 10 SECONDS LATER. Like somehow not only was he preventing me from loading (because on my end my client said my game wasn't starting because he hadn't loaded), but I was also preventing him from loading (because as soon as I got in, his loaded).

What's the most frustrating is that there was nothing on my end telling me I hadn't connected - on my end it looked like everything was normal and I was waiting on someone else to start the game and nothing was wrong.

(The least frustrating part is that despite the huge disadvantage I still went 4/0/3 in Lane and support only died once in Lane, and we still won the game ;) )