I'd like to see what Crafty's official response is, but I'd go with "The distract affects all three, but only one is fixated". It's more inline with other things in the system - Sneak Attack and Critical Hits only work on the first hit of a multi-hit attack, and this seems fairly similar.
As written all three are fixated. Also, each target is rolling separately versus the single Distract roll and the sneak attack and critical hit things are explicitly called out, so it's not necessarily a general rule.
OK, now that I've played FC a few times and seen this in action, along with reading how other tricks work, I think I know what my problem with it is. Almost every other trick has some sort of "flaw" associated with it, either a limited number of uses per scene (based off of action dice or # of Same type feats) or failure penalty (flat-footed, etc). But as written, a player (with an attractiveness of 3) can tie up to six minions per round (two distracts per round), for three separate rounds, for a total of 18 minions in three rounds. Which gets even higher as the attractiveness goes up. My thoughts are to tie the use of the Yowza! trick to the number of style feats of the character. However, to throw my player a bone (since she didn't design her mage with a lot of style feats in mind), I was thinking of tying the number of uses for her (specifically) to starting action dice until the number of style feats outstrip them (freely admitting that might never happen).
Or maybe I'm overlooking some flaw that happens at later levels. I mean, I know the fixate isn't always successful (no major downside when that happens), and each target gets a chance to shake it off. In this instance, my players were 3rd level and it was the Raveners from "The Darkest Hour" (undead could be fixated, who knew) and they pretty much had to role a 20 to come out of this.