Employment Standards should be the first thing done. They're usually very helpful with cases.
Not that I'd recommend this route, but uou could always tell your friend that she should tell her boss that she'll simply sit in the lunch room for her every shift until she gets paid. Surprisingly, that worked for a friend of mine after his boss didn't pay him for a month and a half. But exceptions =/= the rule, I've noticed.
But seriously, BC Employment Standards should be the number one priority for her if she wants to get paid.