I have to disagree with you on several key issues. For example, the "horse's mouth" is extremely likely to be biased in the horse's favor. If, for example, this local government had a reputation for corruption, or inefficiency, or waste, their own website and other government bodies' would be the last places to find references to that. Besides, primary sources cannot serve as an indication of notability. On the other hand, Wikipedia is independent, but it does not consider itself reliable.
The article's content is not really supported by the sources either, and I think at times it's simply wrong because you took too much poetic license. For example, "beautiful ecosystems [...] valued by all British Columbians" - really? There's not a single person in British Columbia who doesn't value these ecosystem? So the article would have to be rewritten significantly to remove editorializing, personal opinions, hyperbole and the like.
So in summary, it may well be possible to write an article about the Islands Trust - but it would have to differ from this one in sources, tone and likely content.