In a perfect world maybe ;) But when it comes to xbox or ps3 development there are more important things like shader counts, texture lookups etc... Also I like to have 100% control :)
That's why I shared it on GitHub, I encourage everyone to enhance it or make a better FX with it. Texture Lookups sounds a great approach yet currently I don't have time to do so.
Don't you have just to put texel lookup to nearest in configure direct3d ? Mipmap to none. If it doesnt work, maybe you've overriden direct3d parameters in the Nvidia desktop manager (or ATI thingy)
Turn off filtering in the viewport. Customize -> preferences -> viewports panel -> Configure driver on the bottom. Change the bottom settings for texel lookup to nearest. Turn off mipmapping if you want as well. googogogogogo
In this case i would say thats not the case for offline rendering. There is no per face assignment happening in the background. Doesnt UDIMs in Unreal work like virtual texturing. One giant texture and a lookup table?