No, but I can still call bullshit like a poker player against someone claiming to have a royal flush. He might really have it, but I know the odds are heavily in my favor. This claim is made too strongly and too soon (maybe that's the fault of the media and not the scientists involved.) It is very hard to prevent contamination, something which has confounded the best and brightest at NASA time and again. I also know that when people say it's impossible for particles of that size to get up to that altitude, they are making a lot of assumptions about a very complex system. It's very likely that the correct explanation is human error, either in decontamination or in flawed assumptions.