Inside, the guard calls "Next" and despite the fact that Hastings has been at the top of the stairs for a while AND CAN SEE THE LAST INTERVIEWEE LEAVING, he looks like this is a surprise. Inside, he tells Windmark that he's a quality assurance engineer; he doesn't report directly to Nina, although he sometimes does indirectly. Windmark starts to tell "Mr. Hastings" that he believes him, but when Hastings corrects him that he's "Dr. Hastings," Windmark suddenly seems to change his tune. It's a moment that plays weirdly to me, because you'd think that Windmark, A) would have read Hastings better initially and B) wouldn't be ready to let anyone here go after such routine questioning, but on rewatch I guess the point is that Hastings was telling the truth about being a doctor, which gave Windmark a reference point to contrast with the lies he's told up until this point. (I don't know why I'm on about it, anyway; you could have picked out the fact that he was lying from space.)
Astrid gives Peter instructions; after some more grousing from Walter, she succeeds in blowing the lock.
Now Windmark is asking the tough questions and decides that he doesn't believe Hastings, so he has him restrained and orders for the dismissal of the rest of the warehouse staff, because of course Nina couldn't have had more than one co-conspirator. Meanwhile, in the storage area, the Fringe team accesses the database, learns where the relevant equipment is being stored and grabs it without delay. While Walter is confirming that it's the right stuff, Olivia happens to look across the room and through a glass, she sees Hastings being interrogated. She urgently relays the news to Peter...
...while, from the high frequencies we're hearing, Windmark is definitely inflicting some kind of pain on Hastings. Windmark ascertains that Hastings admires "Dr. Bishop," and you'd think that Windmark would hurry up and get to the information he needs, given that Hastings' head looks like it might explode like an overripe cantaloupe at any moment. Oh, okay -- he asks where the fugitives are and it looks like Hastings can see Olivia just as she can see him, but maybe it's a one-way glass, since he says he doesn't know, and the tears that look like they're being forcibly pulled from his eyes suggest he no longer has the wherewithal to lie.