Dear Pawan,
Hope your father turns well soon.
I am not sure pls seek confirmation but most likely - Fortis heathcare is not an approved Hostipal u/s 17(2).
As a result of above the reimbursements in excess of Rs. 15k becomes taxable perquisite for specified employees.
Now if your father is getting any pension or is working in a private sector and his annual salary exceeds Rs. 50k then your father steps into the shoes of specified employee and the above reimbursement becomes taxable in case of your father OTHERWISE(i:e if your father is not getting ANNUAL pension &/or salary in excess of Rs. 50k) THE SAME IS EXEMPT.
It will be taxable under head "Salary" i:e 4,85,000 {5 lacs-15k}
Unfortunately, no special avenues to save tax in such case - If eligible investments were made before the PY then the same can reduced from the above Income.
If Fortis Hospital happens to be approved u/s 17(2) then the entire receipts will be exempt.
PS:- Though you wanted an expert to reply but pls excuse me on this.....