Ruling Mew-Ex and Dimensional Valley

[Colddy]

If Mew-EX and Dimensional Valley are in play and Carnivine is in the bench, can Mew-Ex use Carnivine's Ambush Bite just with a Grass Energy?

I mean, do dimensional valley effect aply to Mew-Ex using attacks from non-psychic type cards?

PS: The Carnivine's Card is just an exemple.
PS²: Card scan and translate are in Spoiler.


Mew-EX

Spoiler

Dimensional Valley Stadium

Spoiler

Each player's Psychic Pokemon pays 1 [C] less to attack.

This card stays in play when you play it. Discard this card if another Stadium card comes into play. If another card with the same name is in play, you can’t play this card.

Carnivine

Spoiler

 

[Mora]

Yes because Mew EX is a Psychic Pokemon and is attacking, even though it's using a attack from another Pokemon.