580 and LineageOS: and way to disable hardware navigation keys?

[krakout]

I use my old 580 for my little kid to play a single game. The tablet is otherwise locked using a Kiosk app. That app can override the navigation keys, however it does that with a slight delay - you press Home, for instance, when the game is playing, and the OS tries to exit to Home; the kiosk app intercepts that and returns to the game, however this kind of messes up with the gameplay.

So, is there a way to disable the navigation buttons at OS level?

Thanks in advance, any help greatly appreciated!