Well, your opponent resigned, so that is all the really matter, though I guess it is possible the system resigned the game as soon as the account got closed.
As to why an account gets closed, the site doesn't normally comment on that, other than what is actually posted on the account closure reason on the profile. That profile says it was closed for abuse, so it was not cheating related; that would be closed for Fair Play Violations.
I just had this game:
https://www.chess.com/live/game/2567722116
The game was full of mistakes by both players. I was lost in the end position despite being an exchange up. My King is subject to mate threats (interesting position).
Suddenly my opp 'resigned'. His account was closed due to misuse according to chess.com.
I wonder why, as it seems he did not cheat in this game. he made some big blunders. Can some admin say some words about it? I dont want a win when i dont deserve it :-)