Logging in with username/password works quite fine. Okta will redirect back to our SaaS app. However clicking “Signin with Google” on the Okta page leads the app to redirect back to the Okta dashboard, not my SaaS app:
How did you set up the “Sign in with Google” button? It doesn’t sound like you are letting Okta’s Routing Rules handle the login flow.
If you were, you would see the desired behavior: users logging in via SP-initiated flow are able to federate into Okta through an external IdP and then are redirected back to the target application upon completing authentication into their IdP.