Thank you very much for letting us know, please change the method to this:

    public function toTableArray()
    {
        if ($this->count()>0) {
            $result = array(
                array_keys($this->rows[0])
            );
            
            foreach ($this->rows as $row) {
                array_push($result, array_values($row));
            }
            return $result;
        }
        return [
            array_keys($this->meta["columns"])
        ];
    }

The fix will be applied.