The products you purchased from diviextended.com or Elegant Themes are completely identical. There are some differences on the basis of the platform which are different file names and the license system.

Purchased From Elegant Themes

Elegant themes have their own license system. The product comes with yearly updates and support and needs to be renewed yearly in order to keep getting updates and support on ET.

If not renewed, the product will continue to work but updates won’t be available for it.

Purchased From DiviExtended.com

On DiviExtended.com you get a lifetime license but with a choice between a single site and an unlimited site(extended license).