Match forfeit due to red cards?

A local UPSL match was a 3-3 tie in the 90th minute. One team already had a red card, they surrounded the ref to dispute the latest goal and got multiple other red cards for dissent. The ref then called the match as a win for the other team.

Can a ref award a win? My assumption was because of the lack of players? But unsure what circumstances they can call a forfeit?