Adrian had been in a maximum security cell and was informed that he had someone coming to talk to him. He'd been thinking over and over in his head trying to figure out what he should have done different. He knew that the way he did it was not the right way.
Brought out of his cell in shackles and with several heavy duty guards he was taken to a room where he was chained to a chair and than chained to the floor and wall. All the restraints were believed necessary because of how strong he had become. He looked to the floor up until he heard the door open. He was the only survivor of the SHIELD base at Hawaii and it was documented from his statements that he'd not only nearly assassinated Madam Hydra but had wounded and then been readily defeated by the Red Skull. He hadn't actually claimed Stockholm Syndrome, he'd noted that HYDRAs initial observation of him while captive was that he was suffering from the Stockholm Syndrome.
If he didn't say what HYDRA wanted to hear he'd have had Doctor Faustus going through his mind followed by a bullet. There wasn't a whole lot he could have done under that pressure. HYDRA didn't need him alive to find out what he knew and in his own defense he'd ceased getting any information not immediately vital while he was in Hawaii. He'd given HYDRA false information designated by SHIELD as decoys. Structurally unsafe helicarrier blueprints, weapon loadout charts that were outdated and obsolete. He even tried to make a convincing act of holding back the Avengers after his injection. With his skillset he should have never missed every single shot. He'd bluffed Baron Von Strucker into running away and had attacked Red Skull's Schwartzgard troops and helped cover the Avengers escape.
People could call him flipping, but the fact of the matter was that he was scared out of his mind and trying to do the right thing. He'd never be trusted by anyone who hadn't gone through what he had been through.