Discovery 3rd party claim-too much to ask of

In July of 2022, one of our vehicles was damaged in an accident caused by a 3rd party. It was a rear end crash, did not seem that bad. after all relevant information was swapped and police reports done (3rd party admitted it was her mistake) our broker was contacted and set the ball in motion. My wife owns this business and I, her husband, was out of the country on contract. The assessor wrote the vehicle off to my amazement. My only responses on all the email correspondence, that I received, was please make sure the full balance is settled with the bank and that it was a third party error they are responsible. I need to clarify one thing, my wife runs a relatively busy business, her skills in dealing with things like this are not good and she really depended on the broker and the insurer to act in her best interest, as I was not available. There were emails sent between broker, insurer and my wife on a settlement. I once again reiterated that the full balance had to be settled at the bank and the insurers need to make sure this happens, because it is a 3rd party claim. At some point my wife must have accepted the settlement not knowing that it did not cover full loss of asset. She received a letter from the bank stating that the insurer had settled X amount less the excess and there was a balance of around R18k outstanding. My wife did not realise this at the time, but under these conditions the 3rd party pays the excess and settles the retail value of the vehicle. well this never happened. When I returned from contract in May 2023, I was informed by our broker that there had been a change in the name and ownership of broker but we were still with Discovery, we had a meeting with the new Broker around August of 23.. My wife showed me the bank letter, for the first time I was now aware that we were still paying the bank for a "written off"vehicle. You cannot script this, on our way home on this very same day, our very own vehicle with the same number plate was on the highway near where we live. It even pulled off into our village and went to the local service station, we pulled in behind it and spoke to the "owner" he bought it on auction and had the minor damage repaired (I am seeing massive **** here). he was in a hurry and left. seemed like he was edgy. I got hold of the broker and asked him to investigate further (over a year later from original claim). He came back to me to tell me that Discovery did not even contact the 3rd party, and this is important to note, that discovery failed to track down the 3rd party. Well I lost the plot, this is unacceptable, they said no-one answered so they processed the claim through my policy, hence I had to pay the excess, what on earth. That same day, I got the 3rd party driver lady's number and called her, she answered no problem. She said, now remember this is 14/15 months later that she wondered what happened as no-one contacted her after the accident. My word, no-one contacted her. Please also at no point in time did discovery let my wife know that they couldn't contact the 3rd party, why would they not try her as she dealt with the lady? I found out that she was driving a company vehicle, of a company that was also insured with discovery, oh my word really, and after my broker took the matter up with discovery, the excess was paid back to my wife now almost 16 months later. But there is still 13K outstanding which discovery are not interested in retrieving. After much screaming and shouting I was called by a legal guru from discovery who just hid behind legal jargon and failed to acknowledge the poor performance and errors made by the insurer discovery. She had told me I should approach the ombudsman, that is how they deal with their paying clients. I have asked for the company policy on dealing with 3rd party claims to show negligence on their behalf, i have also requested the timeline of events from inception of the claim, neither have been sent to me, they are hiding something and I want action and my R13K back to settle the bank. Discovery are not a service oriented company at all