When Alex is brought in for questioning, he's quiet, diplomatic and as respectful as he can manage while as tired as he is. At least he's clean and dry by now.

From what he's seen from his cell and heard from the people who would talk to him from them, the newcomers are new mouths to feed these people didn't ask for at best, and potential threats at worst. As much as he's lived his life back home in secrecy, he doesn't see a lot of use for it here.

So he answers questions in the interrogation easily. Talks about his life, his upbringing, his glancing familiarity with interdimensional theory and a career in what is more or less equivalent to xenozoology. With the exceptions of the names and present locations of any of his family members, he more or less makes himself an open book to Captain Childe, assuming it will be easier for both of them that way.
He tries to make it as clear as possible that even as an unwilling stowaway, he'll earn his keep since it's the best way to stay alive, and he can only get back home if he does that much.

After he's told her more or less everything, he sits back, sighs.

"What are you willing to tell me, Captain?"