The one we have is issued by the State Government (civil marriage doc) and we got 2 originals. This contains a long certificate ID number which is unique to our application.
Yes, we will be using VFS and they mentioned "Certificates can be original certificate or a copy with original certified by MEA". If they are returning originals (which they should), it's better to hand over the originals for their review.
. So, I'll write up (1) an invitation letter from my company addressed to the Thai Consulate and (2) get an original letter from BOI stating the dependent status.
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