Tiebreaking settings

Hey there. I’ve been using the plugin for a long while and I’ve made plenty of modifications (some of these I’ll be glad to send over, I’ll contact you about them later), but among the things I haven’t been able to figure out in the plugin is the “tiebreaker” calculations the plugin supposedly does, according to this page: http://www.wcp.net.br/group-tables/.
I’ve found some situations where the plugin keeps saving goal data even though the points in the regular ranking rules end up as a tie. How and where does the plugin calculate who goes as the first and second team in the group phase?

https://wordpress.org/plugins/world-cup-predictor/