Answer: you have not stated any question from your story.
But let me assume your question was
"IS THIS SELECTION PROCESS (THE USE OF SOCIAL MEDIA ACCOUNT TO CHECKMATE THE BEST CANDIDATE) IMPLORED BY THE MANAGER, AN ACCURATE OR ADVISABLE MEANS OF SELECTING THE BEST CANDIDATE FOR A ROLE"
THE ANSWER IS YES.
Explanation: in hiring a personnel, when all intelligence and experience in the job role has been screened, the next things to screen in a candidate is his/her lifestyle and behavior. This lifestyle and behaviour can also be seen from your social media posts. People tends to post what their feel, and remember the proverb " what you feel is who you are" because out of the abundant of your heart your mouth speaks. The manager has used the best means to determine his best candidate after screening their intelligence and experience.
ON THIS NOTE, I WILL ADVISE YOU TO ALIGN ALL YOUR SOCIAL MEDIA ACCOUNT, WITH YOUR CAREER GOALS, TRY TO REMOVE ALL IMMORAL POSTS AND INDECENT POSTS.
hope this answers your question.