HaHa! Very interesting
This probably doesn't happen very often..

Hmm, how does chess.com calculate tie breaks?
You had a higher average opponent. Seems you should win.

Appearantly just the tiebreaker from pointsscored, and no second (or 3rd) decisive factor.
I checked the tournament: normally 1 person would progress.
There where 4 groups (4x4)
4 from our group continued and 1 from the other groups. Then we splitted up in two groups of 3 and 4 people. From those groups 1 went to the final. I ended up winning the tournament, but mainly because my opponent in the final timed out twice... Still pretty proud about it :)
From a thematic Vienna tournament: