Considering how Gotenks worked and how in the movie is portrayed, it is pretty much the case that:
Base Gotenks > SSJ Goten & Kid Trunks
Base Gogeta > Blue Goku & Vegeta
Ikari Broly was slightly weaker than Blue Goku and Freeza needed to kill Paragus so Broly can triumph over Blue Goku, so Gogeta also in ability or power has the advantage. He wins this.