Power Cancel Timing Issue?

[Phazon Elite]

Blissey MT
Alakazam MT

Situation: My opponent uses Kind Egg to return however many cards to his deck, and begins shuffling before I have a chance to announce that I intend to use Power Cancel.

Question: What happens now? I know that, as per this ruling, I would have had to announce Power Cancel before any cards were returned to my opponent's deck, but unlike Claydol, this error is not easily reversible.

Alternatively, suppose I announce Power Cancel before anything happens to my opponent's deck, but my opponent does not notice (or care) that I did so, and continues with Kind Egg. What now?

Thanks in advance.

-Marvin

 

[PokePop]

You would need to call a judge over and let the judge determine what penalties are to be applied.
This is not the kind of question that can be given a blanket answer.