Because the reference to the Jurassic Park jeep isn't quite enough, Zach and Gray manage to, in a way that's not properly explained, get the decades-old jeep working again by swapping out the engine with another random one that happens to be lying around (with that Kawasaki product placement eagerly included, of course). This allows them to drive back to the island. It's straight out of the cheesy Hollywood movie trope book, where the ridiculously intelligent kids do something impossibly smart and technical that no regular child of that age would be possible. It's just kinda annoying, and also further builds the case that Ty Simpkins might as well just be reprising his Harley role from Iron Man 3.
Stay at home dad who spends as much time teaching his kids the merits of Martin Scorsese as possible (against the missus' wishes).
General video game, TV and film nut. Occasional sports fan. Full time loon.