It's been a while for myself, but I do believe the voucher was sent via e-mail so if you put your US hotel address and pay with paypal you should be fine.
I agree that I would wait for the $2 for $25 voucher. Make sure you look at the minimum spend requirements and understand that gratuity of 18% is included.
I think that the vouchers are refilled at the beginning of each month and you will typically find the deepest discounts at the end of a month. That being said, availability for all vouchers may not be there at the end of a month.
I've used this at house of blues and BB Kings with no issues.
Bon Appetit!!