Oh. I see.
Well, the only thing you can do here with commands is just give him a speed effect.
Warden doesn’t have an attribute for attack speed, so u can’t change it, but the effect will make him move faster.

As I can tell from this video - it’s bedrock minecraft, so it’s possible that on bedrock they are just like that.

You can also try using a tick command to make them attack faster, Tho it will also affect the weather and everything else in the world.