Hey @bygonedream ,
I've checked with the team who have been unable to confirm the exact purpose of the files noted, but they may be related to Match Replays and could lead to your in-game Replays becoming inaccessible if deleted.
We won't recommend tampering with the game files, but these don't appear to be core game related and may require a verifying of the game files if removed.
I'm sorry we're unable to provide more information but if there's anything more we can answer, please let us know!