Ha, technically, going by the actual sentence structure used, "him" is a personal pronoun referring directly to Lowden...
"It's been rumored that [Lowden] is on the shortlist. We're going to find out pretty soon, aren't we? Because they have picked him. They have made their choice, but they have not announced it yet. So my fingers are crossed for Jack."
But yes, Oldman almost assuredly means "they have picked [the actor who is going to play Bond]." Even though that's likely not true, as most credible reports stay they're still narrowing down the list / haven't made their final decision yet.
"It's been rumored that [Lowden] is on the shortlist. We're going to find out pretty soon, aren't we? Because they have picked him. They have made their choice, but they have not announced it yet. So my fingers are crossed for Jack."
But yes, Oldman almost assuredly means "they have picked [the actor who is going to play Bond]." Even though that's likely not true, as most credible reports stay they're still narrowing down the list / haven't made their final decision yet.