Steam Common Redist

I have 4 UE4 games on Steam. And from Steamworks I check Visual C++ Redist to true for the players to have it installed.

But From all those games I am constantly getting negative feedback that they can’t have it installed since it appears already installed and they can’t run my games.

Is there any solution for this? Can I safely uncheck the Redist from Steam? What happens then?

Please help, I am losing many customers.