The CEO is the guy in the middle in the left photo. The photo on the right was taken the same night, possibly by the CEO, but certainly uploaded by him. At the very least he had no problem with posting it publicly, and has decided not to remove it over the years.
As of now, finding the Flickr page is as simple as searching for “CEO NAME Flickr”. His name is in the OP article and easily found elsewhere online by searching sticker mule ceo.