Good Morning Frank
Reltio PS haven't developed a recipe for either Workday or Entra yet - however within RIH if you look at the Workato community recipes there are integrations already created for Workday:

One of these should be able to give you the head start you are looking for!
I wish you the best of luck with your development and if you get something working, please share the Manifest with others here on the Reltio community!
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Paul Lawrence
Technical Delivery Manager
St Neots
United Kingdom
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