My method would have involved getting the die position in the world when you want to check the value and sending a line trace down from the sky directly above it. The line trace would return the material from which you could get the texture and if the texture is this texture, then the face up is this value. That works if you have separate textures per face. If you’re using a single texture, you could return the hit normal and say if the hit normal is within this vector range then it’s this value.
Of course, there are so many different ways to handle this and others in this thread have thrown superb ideas! even your 2D UMG implementation would work. It’s absolutely possible to switch out UMG textures at runtime, so if that’s an easier way to do it for you, it’s 100% possible.