Theme Customizer not loading JS for live preview

Question

I am currently working on adding options to the theme customizer. For the last two hours I have been trying to get the live preview working and I am trying figure out why my theme isn't loading the theme-customizer.js file needed for the live preview.

All of the options I have added to the theme-customizer work if I save it and then refresh the page. So I know it isn't an issue with the settings.

I currently have the hook to call the JS file within the customize.php file along with all of the settings for the customizer. I also have a separate theme-enqueue.php where I enqueue the other JS files for my theme.

Here is an example of the hook I am trying to call the JS file from within my customize.php file:

function mytheme_customize_preview_js() {
wp_enqueue_script( 'mytheme-customizer', get_template_directory_uri() . '/js/theme-customizer.js', array( 'customize-preview' ), '20120187', true );
}
add_action( 'customize_preview_init', 'mytheme_customize_preview_js' );

When I check the loaded javascript files within chrome, it seems to load all of the ones I need except for this one. Can anyone shed some light on the situation?