I think I encountered a "Match Remake" Bug

So, when their singed top didn't come to lane I immediately assumed he was afk and was expecting a remake. However, when I pushed to his tower he was right there chilling and instantly their team activated the remake and the game ended. During post game, all their players were connected including singed (as opposed to when an afk player will have an X through their portrait). This is the first time I've encountered this and maybe singed was like connecting and dcing off and on and this lead to a hole in the system that isn't often found. Other players on my team stayed in post game a minute to ask the other team what happened because they had all realized this as well.