They are working correctly as far as I know.
The +N gamble augments are able to pick themselves, as such, if you pick the silver augment that gives you +2 random silvers, the random silvers that you get can be another +2 random silvers, and so on.
Tbh when I was coding I didn't even realize that was happening until a Reddit thread started discussing the meta. And yes, that is indeed OP, I'm still trying to balance the game a bit. I pretend to remove this feature in the future as a nerf, while also make it so "Warm Soup" doesn't appear while you are at full health as a buff.