The project has already been tested and verified to support Sitecore 9.
There isn’t a need to update the NuGet package references, as the APIs in the DLL references are the same across all Sitecore versions (supported by this module). Instead, keeping these versions in the lowest supported version (Sitecore 7) is how we which to proceed to showcase full backwards compatibility.

Thanks for your comment @SaintSkeeta

Somehow when I downloaded the source code it did not let me run it till I updated the NuGet references.

Also, would you be able to help me understand what would be the behaviour of this application in case the package installation fails for some reason?

The project has already been tested and verified to support Sitecore 9.

Can the documentation be updated to indicate this?

I have updated the documentation. Thanks davvves for letting us know it was out of date.