Don't understand why they had seen a refuge there. Looks much more like a bonfire to me.

This wood looks cut in a tip and partially burnt in the other, and the fire makes this notches easily when two logs overlap. Also explains the preservation of the wood, as it was sterilized by fire (maybe minutes before a rain fell or a flood hit). Also the size of the logs (1,5m is too short for a home, but perfect to be carried and stored. Plus the near presence of the classical fire hardened sticks. Is pretty obvious.

So first evidence of "structural use" of wood is a too premature claim. nope. I don't think so.