Unable to activate native church theme after theme update

Okay, I bought the Native Church theme in 2014, when it was released, but I did not use it until last month, so my support has expired. I’ve submitted a ticket to the author, and I hope they will be helpful, but can anyone help solve this problem?

I wanted to update the theme to the current version in order to take advantage of newer features, so I followed the instruction to install the envato toolkit. After I clicked to update the theme, it took longer than usual and I left it to continue without interruption. Hours after, I refreshed the page. It appeared that the theme was updated, so I clicked on activate, then got an error message, something like: cheating uh? theme not installed.

I have tried everything from deactivating all plugin, reinstalling the theme repeatedly, no luck.

Other themes from envato installed and activated with no issues. Only Native Church theme will not. I have even uninstalled both parent and child themes. The theme still will not activate after installation. Please help.