Convert UV Coordinates to (x, y, z)

Given a texture’s UV coordinate, how would I obtain the model/world coordinate (x, y, z) for the mesh that contains that texture?

UV map is unreliable in this case because UV map maps texture on mesh surface, what you looking for is vertices positions, which in C++ you can read here, you should also obtain UV map data of vertecies if oyu need that:

https://forums.unrealengine.com/development-discussion/c-gameplay-programming/7509-accessing-vertex-positions-of-static-mesh

There is also WorldPosition node in materials that apply color based on position data of vertecies, which is a lot better then UV map and you can do computations on both using materials: