I think in that video found on this page (https://www.4dpublish.com/udim-support) shows support for Octane where instructor states 'the answer is yes this works in Octane', but doesn't use the Octanes image texture node which means it isn't really showcasing compatibility with Octane it's just ...

You can work with UDIM workflows in C4D and Octane using 4D Publish: https://www.4dpublish.com/udim-support

It also has direct support for updating textures directly in the Octane Live viewer when painting using the new Paint Brushes...

https://www.4dpublish.com/octane-painting-support/
https ...