The Remake System Bug

Okay so this is my first ever post on the boards and i need to talk about a problem that just happened to me in my last game.

This was my promotional game and our team comp was looking really good. I was waiting for the minions to spawn and i see that our Zac was still at the fountain afk. So I thought all we had to do was remake the game and the problem would be solved. How ever, this was not the case at all. When the time came to remake, it gave me a message saying you can only remake when a player fails to connect. Zac had not moved, talked, bought an item, or anything. So we had to sit in a 4v5 and just take the loss. In the post game lobby it even had the red name, meaning he didn't connect to the game. Why did this happen?