No, the code you're looking at for the $modalContents in the login.php file is displaying the contents of the joomlaLogin_horizontal.php or joomlaLogin_vertical.php files (depending on your SCLogin module parameters). There are two places that the Register link is used: next to the login link for launching the modal (which you are showing above) and from those joomlaLogin php files.but within the modal dialog it seems that you pulling this code somewhere else from outside the template ?!
$this->registerLink = JRoute::_("index.php?option=com_comprofiler&task=registers", false);
$this->registerLink = JRoute::_("index.php?option=com_comprofiler&task=registers", false).'&Itemid=MY_ID';
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