Doctor’s negligence

A doctor from Netcare St Augustine in Durban who performed a brain tumor surgery on my mom at the beginning of last year(2020) is refusing to give her a temporal incapacity leave. I have been calling him everyday since last year but until today we have no paper to submit to work stating why my mom can’t return to work for so long. Now it’s like she has absconded from work. I don’t know what to do anymore as I have been calling them and even sent the form he has to fill and agreed to pay the R2000 he is demanding for the form. I hope someone here can lead me on how to best approach this doctor to fill this form as it is needed at my moms work. She can not afford to lose her job more so because of a doctor who just doesn’t want to fill a form! I don’t understand how now we have to deal with mom’s recovery and also stress over a form that doesn’t even take much time to complete.