How to include PHP in a template via Plugins

[CoffeeLovesYou]

Hi,
Currently, I have this.

PHP Code:

ob_start();
   include('table.php');
   $includedphp = ob_get_contents();
ob_end_clean(); 


and in my template, it has $includedphp to call the PHP file over.

How can I - instead of using table.php, put the PHP code that is already IN table.php in the actual plugin and still use $includedphp in the template? If someone gets the link to table.php, they will be able to see info I don't want them to see -- the table.php is literally just PHP/MySQL table code, I have it calling it to a template to look nicer and in the template, I have it so only Staff usergroup ids can see it, but I can't make it that way for the table.php, since it isn't part of vBulletin. Hope this was clear. Just trying to put the PHP code inside of the Plugin instead of using include('table.php')