I cannot knock down policemen

Hi
I bought A Way Out some time ago and I played with my girlfriend on one computer - she on keyboard, me on pad.
We have escaped from prison and we have a stage with hiding from policemen in the bushes and knocking down two policemen at the same time. There is a problem beacuse my character cannot knock a policeman down. No matter how fast I press X button, I always lose in the end. I even tried with a "turbo" button that imitates a very fast X keypress and even this doesn't help.

We tried to reset the level, reinstal the game, but it's still the same. We can easily knock them down with the keyboard, but it's impossible with the pad. What can we do?