Technically, no.
"5b2) During the repairing of the puzzle, the competitor must not intentionally make the position easier to solve than before the defect. Penalty: disqualification of the solve."
Unless the judge can verify that the corner was originally correct and got twisted wrong (by watching and seeing the actual twist occur), there's no way to know if repairing the corner by pulling it out and replacing it is in fact making it easier to solve than it was before the corner was twisted to begin with. Imagine someone gets to the last layer and has a full LL skip except two twisted corners. If twisting a single corner were allowed to fix it, you could twist one corner "by accident", say "oops, I need to fix it", then twist the other corner to "fix" it. I certainly think this shouldn't be allowed (although it's admittedly a pretty efficient LL algorithm

).
I've always assumed that the rules require that you must twist a second corner to make the puzzle solvable, then you have to solve it normally.