Define an OrganizeWP Entry Pane Item to output the comment count for the current entry.

functions.php

<?php

// Define an OrganizeWP Entry Pane Item to output the comment count for the current entry.
// @link https://organizewp.com/docs/entry-panel/
class MyOwpPaneEntryCommentsCount extends \OrganizeWP\EntryPanelPaneItem {
	function init() {
		$this->name  = 'entry_comments';
		$this->label = 'Comments';
	}

	// Output HTML to the OrganizeWP Entry Pane.
	function render() {
		return 'Comments: <strong>' . get_comment_count( $this->entry->ID )['approved'] . '</strong>';
	}
}