You don’t have to find/download any pixelgrade-care plugin.
The reviewer’s screenshot only shows that the reviewer already has on his WordPress installation a plugin named pixelgrade-care which already uses a version of TGMPA, but your theme (Ojasvi) conflicts with that plugin, by not using TGMPA correctly
You should use a customized version of TGMPA with a text domain, functions prefix, etc - to not generate conflicts with other plugins or builders.
Here you can generate your customized TGMPA correctly: http://tgmpluginactivation.com/download/
Also, always while developing themes or plugins for WordPress you should have wp_debug enabled for logging, here is how: https://codex.wordpress.org/Debugging_in_WordPress
And always keep an eye on that error log file during development…
I also recommend using a plugin like https://wordpress.org/plugins/query-monitor/ or https://wordpress.org/plugins/debug-bar/ or others like them. It shows you slow queries, PHP errors and notices, conflicts, server info, inspect hooks and actions - and many other valuable debug information.
- please note that this is not Envato official feedback, is what I know as an author