I have never had any close encounters with triads despite being of Chinese descent, growing up in Asia in Chinese speaking communities, going to Western countries where there were triads lurking around in some spots. I've seen guys that look like they're from the Triads when I frequented nightspots in Asia and the West lol... they always looked scary to me and I never wanted to be involved with it. But am not sure if friends know Triad people...Welcome, and get well soon!
Even though I prefer to give the family the benefit of the doubt, Triads and mafia and such are so interwoven with daily life in Vancouver (even among folks who seem respectable in all other senses) that I can't outright discount that possibility. I'd also like to claim with confidence that gang-related actions tend to happen close to home, and that it doesn't make sense to follow someone's daughter to California to harm her there, but there have been cases in the media (such as that shooting in Nuevo Vallarta awhile back) where Vancouver-based gang violence has happened a long way from Vancouver. So: I hope it's not the case, and I don't mean to drag a grieving family's name through the mud, but it isn't outside the realm of possibility.
Its interesting you mention the triads though... her family may have had to pay protection money being that they worked in the restaurant business... but then again, triads don't operate everywhere. They have turfs, and I'm not sure whether her family were involved. Anyway, interesting suggestion... though I think so far there have been no clues that point to their involvement and like you said, its quite unlikely they'd go to the trouble of trailing her all the way to LA... unless maybe her family are some kinda of bigshot players in the triad scene... otherwise, seems hardly worth it for them going to the trouble of killing her this way.