Having looked again at MOT history first MOT was in 2006. 3 years from first registration would be 2005. You say GOV vehicles don't require an Mot, I think this was with the fire service for 4 years and had its first MOT after 4 years from first registration, for sale to private ownership.
It has had 5 previous owners from the current owner. We may need to stand down the arse kicking team pending further investigation.
Johnblackers who asked the question has not returned to the site yet from asking the question if he does he may be able to fill some gaps for us to help more.