Checking a ban or case for leaving without visa cancellation

How can one check if there is a ban or abscondment in Dubai if not in Dubai?

Son had to leave and couldn't get visa cancelled, as he had to leave urgently due to medical reasons.

Checked online and residency visa is still active till next year but doesn't want to arrive in Dubai to be fined or arrested.

He has been out of Dubai for more than 6 months and wishes to re-enter in Sept. for a visit. He is a British Passport holder.