View variable

Hello and thank you for this great plugin!
My theme has a default counter which is not accurate and I want to replace it by this plugin.
I found the code in my theme as follow:

$output = '<span class="fa fa-eye"></span><span class="c5-views">' . $this->custom_number_format($count) . '</span>';
        return $output;
    }

I believe the counter is this portion:
$this->custom_number_format($count)
But when I replace it by:
get_post_meta( $post->ID, 'jetpack-post-views', true )
It doesn’t print anything.
Your help is highly appreciated!

https://www.ads-software.com/plugins/jetpack-post-views/