I went with my wife who is a Thai National to get a police clearance certificate for a job in the UK. They required me to write a letter with the reason for the check. So I am fairly sure they will want a letter from the embassy of the country you are going to work in confirming the need for the check. You could always call the embassy to ask them. But alternatively take the letter from your new employer that tells you why you need the police clearance certificate from Thailand. That may work. If it does not the police clearance office will explain what you do need. It took 2 weeks for ours to arrive by post. Good luck.
you may well be right Wylie. I was double miffed because at the same time they lopped 5 kg off our baggage allowance it was 30 kg for years but on the new tickets it was reduced to 25 kg and at check in they would not allow anything over the limit so I had to pay for excess baggage too. I will think twice before I use them again.
I see a lot of people saying use an agent. When I was waiting outside a Kasikorn Bank for my wife I saw a very large sign inside in English that said It is against the law for someone to open a account for another person. So how can the agencies do it legally?
Same happened to me with Qatar Air. I changed 2 tickets from Feb to March and although there was no actual change fee it cost me an additional 140 GBP for each ticket to do it. I just had to pay it there was no choice really. To cancel and book new tickets would have cost much more.
I was just coming from the angle that if not being married was the problem it would be possible to get married. Maybe there are alternative visa types you could consider depending on how long you need to be in Thailand and what you need to do there. Best of luck.