Happened to stumble upon what might be a bug for PBE match history, although I do not know if it would in any way influence the live match history. With the PBE match history, whenever I attempt to access a recent match (my own or a friend's) it sits loading for a little bit before reading:
> Error: 500
> Application Error
> An error was encountered.
1. Go to PBE Match History (Either by accessing it through a recent game in client or [Going Straight There](http://matchhistory.pbe.leagueoflegends.com/en/#match-history) .)
2. Wait, Receive Error: 500.