Conflict with Learndash/Woocommerce- Warning: Illegal string offset ‘post-type’

Hi,

I found a conflict between BadgeOS Community Add-on and Learndash/Woocommerce.
The issue created by the conflict is described below:

I am using Woocommerce to sell learndash courses! After an order is being ‘completed’ (not ‘pending’ or ‘on hold’ or in other status), my site is showing warnings in the top of the website.

Warning: Illegal string offset ‘post-type’ in /wp-includes/class-wp-list-util.php on line 157

The warning is being shown only to the user who purchased the product. Here are some screenshots: http://imgur.com/a/Y2FWf

And this is the code where the warning is coming from:

public function pluck( $field, $index_key = null ) {
    if ( ! $index_key ) {
        /*
         * This is simple. Could at some point wrap array_column()
         * if we knew we had an array of arrays.
         */
        foreach ( $this->output as $key => $value ) {
            if ( is_object( $value ) ) {
                $this->output[ $key ] = $value->$field;
            } else {
                $this->output[ $key ] = $value[ $field ];      /**** line 157 ****/
            }
        }
        return $this->output;
    }

screenshot: http://imgur.com/Yxo9NpR

I really liked the features of BadgeOS Community Add-on and don’t wanna uninstall it. How could I fix this? Thank you.

I double checked and the issue was really with this add-on.