Maxperson
Morkus from Orkus
Genre fiction is rife with drafty old castles full of eerie noises. I haven't suggested anyone invent a hurricane to explain a failed DEX check. The simplest explanation is that the golem moved slightly, and there are any number of explanations for that. Just pick one.
Sure. Aliens could have beamed down and hit the golem with an anti-golem destabilizer. Reasonable explanations? Not sure common as you make out. A drafty castle and those noises are from other things like creaking timbers and other things that would make noise. The drafts don't make noise unless the wind is strong, or the author doesn't know anything about wind.
I cite dex and golems. You seem to be confusing slow with bumbling incompetence at moving. Do you really require PCs with an 8 dex to trip and stumble whenever they walk. Do you force them to knock over drinks with imprecise arm movements? I suspect not.I haven't looked at the fluff text you seem to be referencing, but the golem's 9 DEX very much calls into question the idea that it has full control of its movements. Perhaps a citation would be helpful?
Also, I think piling up twenty boulders in the shape of a golem and keeping them standing on their own would be a difficult enough task without any wind. There's a reason you don't see a lot of free standing statues around that aren't firmly attached at the base to some kind of anchoring mechanism. It just wouldn't be safe!
The boulders would quickly settle in and stop moving.