Having trouble with SendEmail localAPI request

[TBroMEM]

RESOLVED: It did not like the 'customtype' defined in the postdata, give I supplied an existing template (I suppose). Remarking that out resolved (updated below).

This is the code I have in place. It is triggering after AfterModuleTerminate, but not sending email and logging activity.
In the logactivity result, the values for $serviceid and $clientid are showing anticipated values.

I am trying another pass with 'customtype' => 'product',  remarked out.

Any ideas. I only recently added the $adminUsername to see if it would resolve but same issue. We are on 8.13.1.
 

<?php
if (!defined("WHMCS"))
    die("This file cannot be accessed directly");

function send_termination_notice($vars) 
{
	try {
		$serviceid = $vars['params']['serviceid'];
		$emailtemplate = 'Service Termination Notification';
		$clientid = $vars['params']['userid'];
		$command = 'SendEmail';
		$postData = array(
			
			'messagename' => $emailtemplate,
			'id' => $serviceid,
			//'customtype' => 'product',// functions properly with this parameter remarked out
		);
		
		$adminUsername = 'admin.usersample'; // Optional for WHMCS 7.2 and later
	
		$results = localAPI($command, $postData, $adminUsername); 
		if ($results['result'] != 'success') {
				logActivity('Termination Notice failed to send for serviceid ' . $serviceid . ' for clientid ' . $clientid . ' by hook send_terminatio_notice...');
		}
	}
	catch (\Exception $e) {
		logActivity("Termination notice failed: {$e->getMessage()}");		
	}
}

add_hook('AfterModuleTerminate', 1,'send_termination_notice');

 

Edited July 31 by TBroMEM
Noting Resolution