Solved. Upon merging my scene to a new max file and re-applying my materials, I was able to process in ORC.

No luck I'm afaid, I contacted the ORC team last week regarding this, but I was hoping to see if the community had any solutions.
I plan to use ORC quite regularly if I can resolve this issue.

Hi Team,

My current project is constantly failing in ORC with the following error: missing assets - a0a69e0897c6932283c2a8771319ce4240f68a785965228dc7041a78f63bcaf1.png
I have searched my scene from top to bottom looking for the missing asset, which does not exist. I can bake my textures fine ...