If you think it is genuine?
Your suggested course of action is definitely the best option Nick.
Having had numerous run-ins with the DVLA. I can tell you from a very well informed perspective. They make the phrase "law unto themselves" look like the understatement of the millennium!
They can & do move the goalposts to suit themselves.
I was once instructed to present a kit car for inspection in the UK. Unfortunately I'd sold it to a guy from southern Ireland.
However he very kindly offered to drive it across the border into NI.
The car was inspected and it passed with flying colours.
But the evil jobsworth bitch at my local DVLA office (it's closed since then) insisted NI isn't part of the UK. Therefore the inspection was invalid.
Obviously that's absolute boll#cks. But she wouldn't admit it & insisted the car came back to the mainland UK!
I tried to escalate the matter to her boss but got nowhere. The buck stopped with her & because I'd laughed at her ridiculous claim regarding NI.
She successfully blocked my attempts to escalate the matter.
That is just one of several shitty experiences with the DVLA.