Calm down. It's not a racist conspiracy.
He was in the news at the Trooping of the Colour because he was the first guardsman to not wear a busby and now he's come to attention again for doing cocaine, which is a lot more common.
The BBC has picked up the Sun's story because it's interesting, which is the definition of news.
If he was a white Yorkshireman in a flat cap at the Trooping that would have made the news too because it's unusual. And if that man had subsequently been caught doing coke that would have made the news too simply because he'd become known as 'the man in the flat cap.'
The others were not identified because they are not interesting. They could be white, black, Asian, male or female but they did not stand out that day. If they did, they would be named.
I doubt he'll lose his job. If we sacked everyone for testing positive for cocaine and other substances I'd be looking at a lot of empty desks around me right now.