WordPress plugins require frequent updates for security patches and new WordPress compatibility. Nulled versions cannot update automatically [1].
Because the plugin was not downloaded from the legitimate developer (wp-rocket.me), you have no guarantee of what was added to the code [1]. Download File wp-rocket-v3.12.5.1-weanulled.com...
Instead of using a nulled version of WP Rocket, consider these alternatives: you are on your own.
You will have zero access to official support channels. If the plugin causes a site crash, you are on your own. Download File wp-rocket-v3.12.5.1-weanulled.com...