I think we're all forgetting an important factor here: KK's state of mind in 2011 compared to now. Correct me if I'm wrong, but I think this period since the Epitaph tour was KK (and the rest of the band)'s longest break from touring since Halford left 20 years ago. We've all heard stories about the road making people crazy, I think it's totally possible that KK was genuinely done with touring when he retired and all this time off has made him miss it. I'm not dismissing the idea that money is a factor or whatever, but why are we assuming the worst when we don't know the whole story? Why be so quick to demonize the bands we love? This is the lighter than air drones thing all over again.
And like Sixes said, it was a hypothetical question, it doesn't even sound like him rejoining is going to realistically happen. They're a little late on that Priest/Maiden/Sabbath tour and if even it did happen, frankly it'd be beyond stupid for KK not to participate.