GSP error: Chilean customer asking for invoice with shipping total from USA to Chile

[chordheadz]

 So I thought I was using the Global Shipping Program since I've never sent anything directly to an international customer. The customer is requesting I send an invoice with the correct shipping charges, as I only charge $3.39 for an 8 ounce package within the USA. The customer lives in Chile in South America, and a USPS estimate is around $22.50. I'm worried about the low selling price of the music CD ($15) and higher shipping costs skewing the total proceeds and the 10% fee ebay charges. In the past the buyer has just automatically paid with ebay calculating the international shipping from Erlanger, Kentucky. I'm worried if I send the invoice I'll be expected to ship directly to the customer and the buyer isn't responding to messages. 

-Does GSP ever have errors?

-If I didn't have GSP enabled and never have other international shipping options is it even possible for an international buyer to make a purchase?

-Should I cancel the order, and relist the CD?