Good hospital treatment, but then the real pain starts...

I have been acting on behalf of my parents, trying to get Life Hospital to correctly submit claims to their medical aid, but they are simply incapablet: 6 claims with incorrect information (amongst many, many others with correct information and successfully processed) were submitted over the last four years with all sorts of basic errors (mostly incorrect name, membership number, email address). Despite my late father (who was largely blind and partially deaf) repeatedly (and now me) emailing and speaking to them to correct the information on the 6 claims (of which 4 are now so old that the medical aid refuses to consider, but still two that could be claimed under the medical aid's 'stale claim' process), they have just been unable to apply any diligence to their claiming and, rather, handed them all over to debt collecting lawyers (who are equally ***********, it transpires). This process caused my father so much anxiety (particularly when summons was issued against him whilst in he was in frail care!) that I am convinced it contributed to his death. It is now just over three weeks since I sent the last followup email to Life's NCRLegal department, reminding them that I still await a reply to previous emails (there was previously some reply, but of no help whatsoever), and pleading with them to submit the corrected 'stale claims' so that my mother does not have to, once again, pay out of her own pocket. Appalling!