This letter can be written by a third party, witness as a statement of evidence to the embassy that the marriage literally took place. This is basically a confirmation letter. This can be modified according to your needs, and circumstances.
Marriage verification by Embassy
5th July (Date)
The Honorable (name of the person)
Ambassador of India
Embassy of India
49-C, Sussex Dive Road
I hope you find this email in the best of health. I am working as (mention your job) at (mention the place with the complete address). My basic reason behind writing this letter is to confirm the marriage of my cousin. My relation to Mr (name of the person who got married) is that I am his cousin from his (mother’s/ father’s side) explaining in detail, I am his (for example Aunt’s son).
I attended Mr abc’s wedding on (mention date) at (mention place). My stay in India was from (mention date) till (mention date). My stay was at (mention the place). His wedding ceremony was celebrated on the following dates at (address).
I am attaching below the booking of the marquee along with the invitation cards , pictures, Nikkah nama, a small CD of the movie, and other receipts of the expenditures that took place.
I thereby, stand wittness that my cousin got married to Miss (mention her name) on (mention date) at (mention address). I hope my attached proves are enough but if not so, you can call me at the number written below for any further details.