This is so strange because I can find no evidence that there ever was a captive nut on any of my hinge pockets. There's a slight nick or deformity on the long slot next to the hole that the nut should be behind, but no evidence of any spot welds or crimps or anything on the hole.
I'd love to see a photo of how this is supposed to look. I could see putting another bolt there that wouldn't get tightened until after all door adjustments are finished... if not well after just because there's supposed to be one there.