Has Delta talked to you about sending the box of wine back to AMS and sending it nonstop to SEA? I think that's probably the plan.

Edit: I don't think Delta can claim release of liability for alcohol (on international itineraries only). This just means that if the alcohol were lost, you could file a claim for compensation. I'm not sure if this liability means Delta would reimburse you for costs incurred to retrieve the alcohol since it's the government holding the alcohol. Basically, you could probably refuse to pay the duty, and since Delta can't return the wine to you, you could file a claim for the cost of the missing wine. I don't think its within Delta's power to get the wine from US Customs for you. I think the passenger with the name on the box must declare it.

I've seen this happen with the Mexican government and a rifle. Since the passenger couldn't go to Mexico City to declare the rifle, the government kept the rifle and Delta reimbursed for the loss.