I think the waterpark has to be an invention, much like IOA's POE or Disney Sea. Franchising a WP would seem a disaster waiting to happen over time otherwise. Mythos would be a great name for a water park, and a great place to move the restaurant. Then there could be a Mythos Hotel. This is what I mean by an invention.
I know things... bits and pieces, but I cannot say them here though I wish that I could. I have no idea what the pieces imply, as they are vague and very unspecific.