When Vince, E, Drama and Turtle leave the theater, Turtle leaves to get the car. A little later when the teenage girls scream, he escorts Vince like the others - when the car gets visible: Vince, E and Drama arrive, Turtle is already waiting inside.
Turte is missing in one shot when the boys come to the pool party, as mentioned in the audio commentary with Jerry Ferrara and Kevin Dillon.
When Vince is on the roof of the house, telling all the teenage party-goers how good their lives are, his T-shirt is grossly sweat-stained. Seconds later, it's clean and dry.
It's not explained how Ari could possibly have known Vinnie and the gang was at the teenage kids' party.
Turtle is using autographed Aquaman DVDs to get seats on opening weekend, at which point a new movie would not already be available on DVD.