So this had me scratching my head for a good hour today. Comparing SampleApp v511 against a vanilla OBIEE 12c install I’d done, one had “Add Data Source” as an option in Answers, the other didn’t. The strange thing was that the option wasn’t there in SampleApp – and usually that has all the bells and whistles enabled. After checking and re-checking the Manage Privileges option, and even the Application Policy grants, and the manual, I hit MoS - and turned up Doc ID 2093886.