He doesn't see the man before he talks but he's not looking for anyone so it doesn't count. Except that maybe it completely does and that he has to work on being always alert. But he's in the Cave and hadn't expected anyone except Batman and that - that really isn't Batman at all. It's some man who's probably around Batman's age but he can't tell who it is and has no idea why he's here.
He turns and stares a bit just to be sure he's not anyone he know and it's really hard to tell through the mask. It's not his Bruce for sure but it's also not his Cave and the more he looks around, the less it is like his Cave.
He frowns and asks, slightly annoyed, "Who are you?" And what are you doing here?