I would say there's first a point in figuring out if you're actually denied, and if so for what reason (by waiting for the latter, not by calling), rather than just assuming it "must" be denied simply because you went to Pending.

Banks sometimes take an application to Pending for the smallest of reasons, like because the computer couldn't figure what would be right CL to give you, 10k or only 9k. .(Yes, it wasn't at Barclays, but at one other major bank I once called in on a Pending card and all they wanted to know was whether 12k was enough CL or whether I wanted to move 1k from another card to make it 13k. I would have been happy with 5k CL in that case, but they couldn't know that.)