It looks bad to me, but did you notice whether there were elites on the upgrade list? The alternative is that 11A is a nonrev who lost a FC seat to a uniformed pilot who was either deadheading after duty or flying nonrev. The deadheading explanation is less likely IMO as deadheading employees are entitled to assigned seats, although someone could offer to take a jumpseat in order to permit more revenue or nonrevenue passengers to get onto the flight, so presumably this would have happened only if the flight had been full, which apparently it wasn't, so my guess is that the pilot was flying nonrev.

You could report this to DL and say that as an elite you're concerned since it certainly looked bad to you.