Bait and switch deal.
This group advertises property available for stay on a couple other vacation sites (which you know). Once you email your contact information the common reply is, "that property is no longer available but we have many others to show you." When in fact the property as listed does show availability, they simply are deceiving you to gather a possible lead.
Upon further searches on YELP and other review sites this organization gets poor marks. Well earned it appears.