Why did I purchase a model from here that fails to convert to any version of UE???

I purchased a model from here thinking I was buying something to use in my game creation. Turns out not to be the case and it fails to convert from any format it has to any version of UE I have installed. What the hell happened to the assets that just went to my library without having to jump through stupidass hoops?

Is this pack in another engine format?

There probably will be an FBX which you can import, maybe?