This new information goes perfectly with the new Quantum Realm suits that are teased at the end of the Avengers: Endgame trailer.
The Avengers: Endgame Instagram trailer aspect ratio features something that was not seen in the YouTube version.
The first Avengers: Endgame trailer had Scott Lang out in front of the Avengers headquarters as Steve Rogers and Natasha Romanoff looked at the security monitor.
It’s not clear how he got out, but the latest Endgame trailer suggests that he brought Hank Pym’s shrunken laboratory back with him.