Sadly that's customer support for you
All I can suggest is that he posts a comment on his ticket every day to keep it alive and also that he screenshots the ticket he has submitted so that he has a record of it. Tickets have been known to be deleted without response. It's also possible that he may receive a nonsensical reply - in that instance I'd also suggest he screenshots the reply and starts a fresh ticket as maintaining dialogue with support personnel like this can drag on without any progress whatsoever.
Last of all keep us updated on here and the gree representatives may take an active interest if they see that your hubby isn't getting any success from contacting support.