Can the apple watch purchased in US still under warranty get repaired outside of US

Does Apple Watch (GPS only) come with an international warranty? I got an Apple watch for my dad from US to bring back to Taiwan. It stopped working and started showing the flashing apple logo after a month. It appears to be the boot loop. After following the hard reset steps numerous times, customer service suggested we contact the repair team. However, Apple repair (genius bar) in Taiwan refused to take in the watch or do any diagnosis even though they confirmed it's under an international warranty. The rep told him to bring it back to US for any repair. I'm puzzled about what can be covered in the international warranty for a 2-month-old watch with valid purchase proof. Has anyone had a similar experience? Or the international warranty is no different from the regional warranty?