Is this the Auth0 Client Library you are referring to?
If so this is not an Auth0 SDK, but a blog that shows how to integrate Maui with the Microsoft IdentityModel.OidcClient.
Glancing at the documentation I would expect this to work for Okta Integrations as well, at least with custom authorization servers. I have integrated IdentityModel.OidcClient with web-apps before and it worked.
Can you provide more information on the issue you are running into?