Current State is below from IGEL Tech Support
I have confirmed that Duo is not a supported method and there are no workarounds. The KB provides our supported methods. Duo can be used for OS12 authentication into sessions. But it cannot, currently, be used to authenticate into UMS.
I hope that clarifies. You will need to use one of the methods provided in the KB for authentication into UMS.
We use DUO Security and would like this implemented as a supported method