Hello.
This game was not made for steam deck.
Performance was not changed since it made for PC's and no one had a problem there.
In all honesty im afraid that if I would give you a key, you would give me a unfair negative for something I never stated it would work on . :(
Since you gave this game a a bad rating on itch for that reason .
Those ratings hurt us more than the public would know.
Thank you :)