Do you know if the DVLA had revoked his licence?
No but at the time?
It is difficult to tell really in this forum.
Certainly it is right to say that there mere expiry of a photo licence does not normally lead to revocation of a licence.
However, the fact that it was not invalid on the police system tends to suggest it had been revoked for some reason.
If it was revoked then he didn't have a licence. It might not have been his fault but he did not.
He needs to get to the bottom of that really before incurring costs.
If the answer is in his favour then he can always appeal. He is out of time to do that now but they are not going to refuse leave in the circumstances.
Can I clarify anything for you?
No, but that presumes the DVLA haven't done it in error or for any other reason.