It sounds like he was a political appointee, and as such would be subject only to “vetting” in the political sense rather than the typical hiring process befitting a modern professional civil service.
Having said that, unless the work is particularly sensitive (requiring a clearance) many government employers in countries with decent human rights and employment law will not check your social media because they are likely to learn things about you there that might bias the hiring process, such as your religion, your sexuality, and so forth.
