Lindeman's is a nice little alcopop, but it's not very traditional or representative of the style. It's made in a traditional way, but then it is pasteurized, heavily sweetened, and force carbonated. Unfortunately this seems to be more and more common. But lambics were often sweetened in the glass to ones taste, like a Berliner weisse, so take it for what it is.
Lindeman's does make a really nice gueuze in their cuvee Rene, which is not sweetened. It very much represents the style. Something to look for in a classic style is the word "oude" in the name, so oude gueuze, oude Kriek, etc. This means that it meets the traditional definition of how it was brewed and should be an indication of whether it's representative of the style. The exception would be beers from Cantillon, which does not use the term "oude," but they're pretty hard to track down in the states.
They are fermented with wild microbes, both yeast and bacteria. By wild, I mean what's in the air around the brewery, and whatever has built up in the barrels over a lifetime of use. Some of these barrels can be a hundred years old or more, so while they are exposed to ambient microbes in and around the brewery, they are heavily influenced by the microflora inside the barrels.