Any refund will ultimately come from the property, not from Chase Travel. The property may need to make the payment through the agency, rather than directly to you, but it's their failure, and they will need to bear the cost. If you have the name of the person you spoke with at the hotel, I would contact them directly and ask if they have been contacted by the agency about a partial refund due to the room downgrade. Don't be surprised if they say they have never heard of Chase Travel because the transaction may have been outsourced to a consolidator such as Expedia.