I think that the issue is the difference between proving to a court of law (or ICC hearing in this case) that reasonable doubt as to your guilt exists, and persuading people in general that you're innocent. As has been mentioned, sometimes this is the same thing, ie irrefutable alibi who proves you couldn't have done it. Other times its more grey than black and white.
In this case, there was damage to the ball. The hearing concluded that it could not be certain that the damage had been deliberately inflicted by member or members of the Pakistani team. As such reasonable doubt existed, and they properly found Inzi (and the Pakistani team) "not guilty". They DID NOT say that Pakistan definately DID NOT tamper with the ball, they just said that the available evidence did not make a sufficiently persuasive case for them to find they HAD tampered with it. I can't think how to explain this more simply.
So, Pakistan were found not guilty and therefore received no punishment, and cannot be said to have been found to have cheated. Practically it is an identical result to saying they were found innocent. But you'd have to be seeing the ruling though a biased point of view to think that it said that Hair had no basis for making the allegation, or that it questioned Hair's integrity in making the allegation.
It found there WAS damage to the ball. If policemen were thrown out of the force everytime a charge they brought was unsuccessful, we'd have no police left.