That's just the thing. Wood at that height could probably be preserved as wood, perhaps 4000 years later. But in order to become petrified, it would have become submerged and buried by other sediments.
Then extremely slow movement of water molecules through that layer would replace the organic material in the wood while maintaining the physical structure of it.
It's impossible to conceive of those conditions on a mountain top. First, you can't bury it in sediment. Second you can't have the waterflow underground to make the replacement happen. It's just too dry or frozen.
The link you provided makes the categorical statement that it's petrified wood, but provides no backup for that claim. So, there's no way to know whether it's credible or not. Extremely unlikely claims need corroboration.
I'm not saying it's not petrified wood. I can't make that determination from the photos. All I'm saying is that I don't see how it could be. It fails the common sense test.
I understand and agree with you. It would make more sense if it was frozen wood instead of petrified wood. We don't know a process for mountaintop pertrification. Doesn't mean one doesn't exist. But their claim of lab tests lacked details and is so far unsubstantiated. It badly needs independent verification.