Holon Transiever

[Magnechu]

At my last CC I went to, in T4, I played a Holon Transiever. I was under the impression that since the discard pile is common knowledge, that I could:
1) Play Transiever
2) Look through my discard pile
3) If nothing was there I wanted, look through my deck
in that order.
However, it was ruled that I had to reverse 1 and 2, so I HAD to take something from my discard pile now. It didn't affect me very much in that game, but I was curious, did the judge make the correct ruling? Or was I right? Thanks.

[PokePop]

Did you communicate what you were doing?
If you played the Holon's Trans and then picked up your discard pile without saying anything, that was an indication that you had made the choice required by the card and had chosen your discard pile.

It would be best to check your discard pile before playing the Trainer.
However, if you did play the Trainer first, you would need to communicate that you are not choosing your discard pile yet, you are just checking it first before making a choice.

Lack of communication on your part forces your opponent and judges to assume you are making the moves and choices required by the play of the Trainer.