Change woocommerce status with callable function

Question

This function is made to be called with ajax through a button click to change the woocommerce order status. However I was wondering if this function could just be called as a function itself for example in an if statement. I tried putting the code inside an if statement but failed. The code needs to work after an eForm submission which changes the status of that order_id

function update_order_installer_status() { check_ajax_referer( 'nonce_update_order_installer_status', 'nonce' ); // we are safe now
// Get all customer orders
$customer_orders = get_posts( array(
    'numberposts' => -1,
    'meta_key'    => '_customer_user',
    'meta_value'  => get_current_user_id(),
    'post_type'   => 'shop_order', // WC orders post type
    'post_status' => 'wc-pending' // Only orders with status "pending"
) );
foreach ( $customer_orders as $customer_order ) {
    // Updated compatibility with WooCommerce 3+
    $order_id = method_exists( $order, 'get_id' ) ? $order->get_id() : $order->id;
    $order = wc_get_order( $customer_order );

    // Iterating through each current customer products bought in the order
    foreach ($order->get_items() as $item) {
        // WC 3+ compatibility
        if ( version_compare( WC_VERSION, '3.0', '<' ) ) 
            $product_id = $item['product_id'];
        else
            $product_id = $item->get_product_id();

        // Your condition related to your 2 specific products Ids
        if ( in_array( $product_id ) ) 
$order = new WC_Order($_POST['id']); $order->update_status('wc-completed');

$order->status = wc_get_order_status_name($order->get_status()); wp_send_json($order); } } }
add_action( 'wp_ajax_update_order_installer_status', 'update_order_installer_status' );
add_action( 'wp_ajax_nopriv_update_order_installer_status', 'update_order_installer_status' );

I tried the following:

if($this->form_id="109"){ $customer_orders = get_posts( array( 'numberposts' => -1, 'meta_key'    => '_customer_user', 'meta_value'  => get_current_user_id(), 'post_type'   => 'shop_order',  'post_status' => 'wc-pending'  ) ); foreach ( $customer_orders as $customer_order ) {  $order_id = method_exists( $order, 'get_id' ) ? $order->get_id() : $order->id; $order = wc_get_order( $customer_order );    
// Iterating through each current customer products bought in the order
    foreach ($order->get_items() as $item) {
        // WC 3+ compatibility
        if ( version_compare( WC_VERSION, '3.0', '<' ) ) 
            $product_id = $item['product_id'];
        else
            $product_id = $item->get_product_id();

        // Your condition related to your 2 specific products Ids
        if ( in_array( $product_id ) ) 
$order = new WC_Order($_POST['id']); $order->update_status('wc-completed'); }