This effect prevents cards stacked on top from being trashed by <De-Digivolve> or other effects, and cards stacked on the bottom can't be trashed by effects such as those that trash digivolution cards.

No, you can't. A "by doing X" condition can't be met if only some of the required actions are performed. The conditions for this inherited effect require you to return the specified number of cards to the bottom of the deck.