Leena - if you want to know if there is a Luis Vilora at the British Embassy in Thailand (it's NOT a High Commission) then use the link I gave you before and ask them on that phone number or at that email address. None of us here are likely to be experts in the staff at British Embassies.
But it's a scam. You're clearly not a high profile music star so no one over here in the UK is going to pay you that much money for a concert appearance. Trust me on this!

Anne