To be honest I don't know what to make of that. Are you trying to add a template called 'inferno_header' to your navbar? Then you'd want something like this:
PHP Code:
$templater = vB_Template::create('inferno_header');
$inferno_header = $templater->render();
vB_Template::preRegister('navbar', array('inferno_header' => $inferno_header));
and then in the navbar template:
Code:
{vb:raw inferno_header}