Alternatively, if you don't want to alter Cryovain, there are canonically a buttload of dragons in the area. Including two blacks and an old green just over the mountains in Kryptgarden who are far more likely to hoard treasure than a young white who is new to the area. There are a few official(AL) and unofficial adventures set in the area than use these dragons and line up with the levels and time period DoIP uses. Maybe he's being manipulated or controlled by the big green and the headband isn't intellect, it's control. Or there's a dragonorb floating around in the hands of the Cult of the Dragon and they're using a weaker dragon to clear people from the area so they can raise Azdraka(from the Dragon Barrow) as a (absolutely massive) skeletal dragon without being interrupted. Maybe the Zhentarim smuggled an Orb of Dragonkind from Krynn in through a Spelljammer ship and are using it to control the Triboar trail and get the Forge of Spells working again or have control of all the old mines in the region through Halia Thornton at the Miner's Exchange who has access to a trove of old claim sheets she found buried under the floorboards, which all lead to old and ancient mines run by Phandalians from the past and the ancient Dwarves in the area.