2 official rulings from Bandai, last ruled Mar 28, 2024. Straight answers to how this card actually resolves.

If my opponent reveals 3 Digimon cards from their deck by this card's effect, does it <De Digivolve 3> 1 of my opponent's Digimon?
No. <De Digivolve 1> activates 3 times, not <De Digivolve 3>. The difference is that <De Digivolve 3> allows you to trash 1 to 3 cards, but <De Digivolve 1> trashes 1 card three times, meaning that you always trash 3 cards (or until there are no more digivolution cards or until the Digimon is reduced to level 3).
Ruled Mar 28, 2024
When this card’s effect returns revealed cards to my opponent's deck, which player decides the order the cards are placed in and whether the cards are placed on the top or bottom of the deck?
The player that activated this effect chooses.
Ruled Mar 28, 2024
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