Did you do your active style and -1 for the master style? Otherwise you will only get templates that are different from the master style.
Not to mention you can't just replace the function with "file_get_contents" - now you have a function named "file_get_contents".
I would play around with the fetch_template_start hook and try putting in the code from the second page:
PHP Code:
if ($template == '<<< FILE >>>')
{
$template = addslashes(implode('', file("./templates/$template_name.htm")));
$vbulletin->templatecache["$template_name"] = $template;
}
(note that $templatename is now $template_name)
Then create the child style '<<< FILE >>>'