I have one mesh, its UVs are laid out in 3 tiles (UDIM 1001,1002,1003).
Do Maya 2019 with Arnold (Mtoa 3.2.11, Arnold Core 5.3.1.1) not support multi-tile texture maps in the viewport? It renders fine, just does not show in the viewport.
The moment I change the UV Tiling Mode to "UDIM" the texture map disappears. By default it only shows the first map on the entire mesh (which is ofcourse only reading one tile for all parts of the mesh).
Btw - I am using aiStandardSurface shader.