Wow, I didn't expect you to write back so quickly.
Your question is complicated.
I know some that have done it in the US. Maybe he should look at the FAA website for advice.
Europe is a whole different ball game and it varies from country to country. He would have to deal with the JAA conversion issue. Many have done it but it come with MAJOR pain and expense. In addition to the work permit...
What about options in Asia? If he is able to get the FAA license, he might be able to get on with a carrier in Asia. Are there any cultural/historical problems with him going to an Asian carrier?
how is his English? Can he pass the new ICAO English language requirement with a level 4? Perhaps the ROK Civil Aviation Authority can guide him to an English language testing center for this test.
Should he go down this path. He needs to develop a plan. In/out of Asia, type of license FAA/JAA. Can he do some of the license testing there in ROK.
Does he have any colleagues in Commercial Airlines now than can advise him?
Good luck,
Lifter
PS: by no means am I an expert, these are just things that for me come to mind. these are also questions i ask some of my USAF colleagues that are getting out now and want to stay or go overseas.