Given that VAR can’t hear them, how do they influence decisions?
We simply don't know this to be fact.
Here are the VAR practicalities from the current Laws of the Game.
The third one confirms that only authorised persons are allowed into the video population room (VOR).
The fourth practicality confirms that the VAR has full access to all broadcast footage - probably to include commentary. Broadcasters will be well aware of this, and the likes of Neville and Carragher commenting on incidents in order to influence officials is therefore quite possible.
Notice the seventh, final practicality which allows the operators to choose what footage is used. The on field referee can request other footage or angles for a review, but how will he know they exist? He will surely think he is being shown the best footage. This opens itself to corruption from within the VOR, and we saw this in the Llorente decision as recently referenced.