Xgv wouldn't just drop for no reason, and I really don't thing people are buying high and selling low (apart from the unlucky few who panic sold). There is something coming, wether it full collapse if the fake news is in fact real, or there's a few people a couple of steps ahead, and know there's going to be a substantial rise. I don't get it, but I'd rather chance losing my 5k XVG than to panic sell and kick myself after a week when it goes up 4x when wraith protocol takes effect.
Please, contact their support, we do not develop this wallet, if the integration works (you can connect the Trezor to the wallet), then our part is most likely working fine and the issue is with their interface. Feel free to share their reply