Stalling payment through requesting burdensome levels of detail

My Mother fell very ill and was recently hospitalised for 16 days. She has an AIG hospital policy, for which I submitted a detailed claim, together with specialist medical reports etc. on 03 September 2020. On 20 September, I get notification that the claim will be subject to medical review, requesting a host of information which will require a herculean effort to track down. On top of dealing with a terminally ill mother, AIG now has me chasing down ridiculously detailed information e.g.: "Complete Hospital file with nurses and doctors daily ward round notes, vital signs, prescription charts, physio-the******s’ notes, etc." It is almost as if they believe that they can prove that the hospitalisation period was unnecessary, despite a draconian medical aid willing to pay for the hospitalisation period? Doubtless AIG are permitted to do this according to their fine print, however the public should know about the dark side of these policies when getting suckered into purchasing them.