TMS part 35: Unexpected reasons

So Bender, Skipper, Phineas, Isabella, Ahsoka, Falco and Q arrive with Dipper and Mabel they learn their parents were killed which Isabella was dead right on. Fortuantly Dipper got a shot of the perepurator which Bender uses to figure out the prepurator with a  chemical dark room. And they figure out it was Mecha Sally. Skipper and Finn tell the twins they can  join in their little adventure