Payplans Using EasySocial Registration mapping fields to MailChimp

I have a client that is using EasySocial and Payplans. When a new user signs up I use the EasySocial Registration for Payplans. This works great. My issue is that when it sends the user info to MailChimp It maps the "Display name" from EasySocial. If I have it set to "real name" it maps that to the "fname" field in MailChimp. Is there a way to map the First Name to the "fname" field and the last name to the "lname" field?

I have a support ticket in with Ready Bytes and their thoughts on the solution are below but is didn't seem to work.

Go to file plugins/mailchimp/mailchimp/app/mailchimp/mailchimp.php

near line 115, you will find the code
$merge_vars = array( 'FNAME' => $user->name);

replace it with below. Also test it and If the require_once condition doesn't work, then please verify it from easysocial team about how to include the easysocial as we don't have much knowledge of easysocial code.

require_once(JPATH_ROOT . '/administrator/components/com_easysocial/includes/foundry.php');

$field =FD::model('Fields');
$data = $field->getFieldsData(array('uid' => $userid, 'type' => SOCIAL_TYPE_USER, 'key' => JOOMLA_FULLNAME));

$merge_vars = array( 'FNAME' => $data[0]['data'], 'LNAME' => $data[2]['data']);


Just as it is done for subscribing the list do it for unsubscribe.