Unless the company was flat out lying in their investor newsletter when they said...
"Justin Bieber filmed four campaign videos this past Labor Day weekend that will highlight upcoming promotions and public service announcements surrounding responsible texting. We look forward to more filming opportunities to leverage our relationship with Justin Bieber."
...and unless St. Clair was on scene (shown in various photographs from that day) just because he had a man-crush on JB, then I'm really not sure what more proof you need.
Justin tweeted it and there are photos of the shoot too all over the Internet. All this has been posted here and on the FB page several times. It has been confirmed by many sources and ones that have nothing to do with the stock.