Wesbank — Retrieval of documents

Many years back my mother had financed a vehicle through Wesbank. There is no outstanding finance on the vehicle. Now that my mother has passed, I am trying to finalize her estate, selling the vehicle being part of that.
As per the traffic department, Wesbank have the vehicle's registration documents to hand. I called Wesbank who advised that I am required to submit various paperwork to them via email in order to get this resolved. Once done (all documents emailed) I had no feed back. Eventually (after numerous emails and calls) I received an email to say that the attachments had not been received and to resend them in. pdf format.
As requested this was re-formatted and emailed back to Wesbank. It has now been a week of trying to confirm that the email has been received and if anyone is actually helping me. I have requested a call from a Manager as call center staff seem to be unable to help, but no call back received as yet.

The automated responses being sent are telling me to log-in as a customer on the website to request my documents back but I was never the customer and have no log-in details. My mother never used a computer and so also never would have had log-in details.

The details forwarded were;

Copy of Last Will & Testament for Daphne Marion Sage (RSA_ID: [protected]) - 9 pages
Copy of Letter of Executorship - Naming Daveron Sawdye Sage (RSA_ID: [protected])
Copy of Death Certificate for Daphne Marion Sage (RSA_ID: [protected])
Copy of RSA_ID for Daphne Marion Sage (RSA_ID: [protected])
Copy of RSA_ID for Daveron Sawdye Sage (RSA_ID: [protected])

The vehicle's details are;

MK1 Fox 1.8 1994
LN: BTN 790 EC
Vin: 16ZRU871388

What else do I have to do to get this paperwork back from Wesbank?