That's almost certainly where Paul's originated from. I've been in contact with the wholesaler over here, who got the shipment from them, and was selling Zachrysia as Bulimulus sp. There is a minimum order of over $1000.
Try bathing gently or spraying them in luke-warm water. It is probably just the journey, they may be a little frightened. Also, it isn't that warm at the moment so tropical snails will probably need some convincing that conditions are stable before they come out to investigate. Give them time, a few of my snails were very shy at first, only to settle in nicely a few days later.