Is this a standalone vRO appliance or vRO embedded in vRA? Could you check if the Kubernetes pods are up and running? To do so, open SSH terminal to the vRO appliance and run the following command:
kubectl -n prelude get pods
By vro 8.0 do you refer to vRO 8.0.0 or 8.0.1?
8.0.1 is patch release and I will suggest to start with it.
Not sure if you have already check it. Looks like another user has similar error which got resolved using 8.0.1
the install media is O11N_VA-188.8.131.5255-15296158_OVF10-2
Did you ever get this resolved? I am seeing the same issue in our lab.
After deploying 8.0.1 appliance and applying the fix from the KB the vco-app container shows as 2/2 Ready, but going to the FQDN URL gives "404 page not found". DNS is working ok on the appliance forward and reverse.
If you get 404 after login and not a login error try manually changing the URL in the browser to https://your_orchestrator_FQDN/orchestration-ui/ after you get to the 404 page.
If this helps could you please share a screenshot of your browser with the 404 error where the current URL is visible?