Sounds like a blown call to me. Blue should not have made a safe call right away, as the runner never touched the bag. However, since he/she did make the call, the defensive appeal would be considered invalid because F3 already did the appeal (inappropriately I might add). Of course, blue seems to have missed that appeal too. In other words, totally screwed up situation.

If I'm wrong guys, go ahead and bash me, but this is how I would handle it if it came up.