Hello CityMedia,
You do no have access to ThemeForest either? You should be able to get the license code from ThemeForest and look it up in our database to get the APEX login name and email.
And if you have access the site which is currently validated, you can get the license code from there. Simply install a child theme which you can get it from here: https://theme.co/apex/child-themes
After the child theme is set up, please add the following code in your child theme’s functions.php file
// Display the license key in the WP Admin panel
// =============================================================================
function display_key(){ ?>
<div class="update-nag notice">
<p>Your X theme validation license key: <strong><?php echo x_get_option('x_product_validation_key'); ?></strong></p>
</div>
<?php }
add_action('admin_notices', 'display_key');
// =============================================================================
This code should display the license key while you are in the WP admin page. You can get the license code so we can look for it in our APEX database.
Regards.