Let's go back to Tesla, where the plot holes are slightly less obvious. Another student dives, but his partner's controller device shorts out, leaving the diver helpless in mid-air. He screams, flails and hits the water with a big splash. Two of the judges give him a 0 while the third judge is apparently so disgusted with this failure that she doesn't give him a score at all. She must be the Russian judge. The Russian judge is always the strictest. "I'm having second thoughts," Zoe says. Well, it's your own fault, Zoe. You should have done the tiniest bit of research into this thing before you agreed to participate. Pilar passive-aggressively (and awesomely) says that's easy for Zoe to say since she already got into Harvard. Pilar, on the other hand, still has to work hard and earn her place there. Also, she's in control of Zoe's movements now, so she doesn't really have a choice in the matter. Even worse, Carter shows up to watch and whistles loudly from the stands to get Zoe's attention. Dads are so embarrassing.
Zoe stands on the edge of the diving board as the announcer says she'll be doing a back three-and-a-half somersault. "Wait, she can't do that!" Carter says to Pilar. Oh, I guess he didn't realize that this diving event had nothing to do with the actual skill of the person doing the diving. Both he and Zoe really need to pay more attention to things. Pilar explains how the sensors work to Carter and then gets engrossed in controlling Zoe's movements. So much so, in fact, that she (along with everyone else in the audience) fails to notice that the pool water is suddenly bubbling. Carter's well-trained eye picks up on it, and he yells at Zoe not to dive into the water. But she doesn't hear him, nor does she have control over her body anyway, so she executes a perfect dive into the water just as the surface explodes in flames. I loved Pilar's "oh shit" face there, by the way. Underwater, Zoe tries to swim to the surface, only to see that it's on fire. Her "oh shit" face is also pretty good. It's not easy to make an "oh shit" face underwater, either. This is why Jordan Hinson gets the big roles that force her to quit this show and the writers to write a rather implausible excuse for her sudden departure.
After the break, Carter springs into action, removing his gun belt and diving into the water. He finds Zoe under there and grabs her while, above the surface, a quick-thinking lifeguard shoots the flames with Eureka's version of a fire extinguisher. Carter and Zoe surface to the cheers of the crowd. We never find out what the judges gave her.