Priceline's method for determining a "star level" is strictly by offered amenities. Refrigerator and free wi-fi aren't on the list. Unfortunately, free wi-fi is only found at the low-end properties -- Hiltons, Marriots, Hyatts, etc., all charge. You said "5" but Priceline classifies this as a 4* property. They don't offer any 5*s in San Antonio.
If there was anything missing from that list, you can challenge them on that point.

The hotel was within the area you bid on, so you don't have a claim there. You have to be prepared to accept any hotel in the zone on the map.

If the property itself was subpar, you should talk to the hotel manager or Marriott.