He is not.
I’ve read the article (link, again: http://www.independent.co.uk/opinion/commentators/fisk/robert-fisk-even-i-question-the-truth-about-911-462904.html) and I’m at a loss at how anyone can be so disingenuous to flat out brand him as truther. The article is much nuanced, it clearly designates a truther (his term is raver) and he separates himself from that (which also he suggests maybe due to some psychological issue) and points out certain parts of the narrative that just simply does not make any sense.
I understand that it is always easier to go along to get along so if that’s your thing fine. But if you can swallow that fiery explosion and burning kerosene destroys steel beams but terrorist passports survive in the debris then I want what you’re on. If you can swallow naming the terrorists only for several of them to show up in various places well and alive, again, great for you. If you can swallow that witnesses saw Mossad agents high-fiving each other on top of the van at the sight of burning Twin Towers and they go free, again, great, I admire your rectitude. But please don’t go around and preach because common sense is not your thing.