I also was just struggling with this issue. For me the ultimate resolution was the username for the SQL DB. We use different permutations of the same userid for each of the vSphere services (vcuser-vc for vcenter, vcuser-srm for etc...). So, obviously I used vcuser-rsa for the SSO install.
As soon as removed the dash from the username, thus using vcuserrsa, I no longer received the "Error 20010.Failed to configure LookupService", and the install completed succesfully.
What a piece of junk.