After the skirmishes between the cadets and the Titans come to a close, the soldiers of Trost see Eren carrying the boulder to the breach and defend him with their lives. Once the breach is sealed, the Scout Regiment arrives to assist in clearing out the remaining Titans.
After the battle, the cadets assist in clearing out the corpses, and Jean finds Marco’s body. Some time later, Eren awakens in a cell supervised by Commander Erwin and Captain Levi, who accepts him into the Scouts.
You can watch Attack On Titan Episode 13: Primal Desire: The Struggle for Trost, Part 9 online for free in the next link: