1. As to the UG on the specific ORD-AMS flight, you've paid $579 and have been UG (I presume). Your miles and the $ associated with the request should now be refunded.

2. As to the other refunds you are due, you haven't explained what they're for. But, presuming they are owed, you can dispute each $ charge with the issuing bank for your CC. This places UA in the position of having to justify the decision not to refund. If UA either doesn't respond or does not properly document the reason(s) for not refunding within X days, you will see your refund through the chargeback process. You will need to file a dispute as to each individual charge.