I am wondering how genuine the letter by Hantuimc is.

It is not possible to have a shortened medical course, and in UK the minimum is five years.

At 27, I wonder what capacity he is working in. He sounds like a general practitioner (GP), although the usual UK National Health Service 'list' (patients under a GP's care) is usually less than 5,000.

The average age at graduation is 24. A year of housemanship is then required, and a vocational training rotation of three years is usually required before one can embark on a career as a GP.

All in, it sounds like a put-on letter.