It's a moot point anyway, as we have solicitor certified copies. The pension manager is actually going to contact the solicitor to check that they are legit.
A while ago my family had a similar problem with a jobsworth making life difficult in a the same way and we were at the end of our tether. We were advised to contact a newspaper helpline and ask them for help. Instant resolution after just one phone call. I think it was the Daily Mirror. Free as well.