Air India — 82 year suffers injury at aerobridge just before boarding, not allowed to fly and not given another passage after recovery

Address:	New Delhi, Delhi
Website:	www.airindia.in

My parents (Father 82+ years old and mother 71 suffering from dementia) were scheduled to fly air india flight ai 0020 on november 16 at 1425 hrs from delhi to kolkata (Yedr 8 and yedr 9) but my father suffered a grievous fall and had to be taken to medanta hospital at the igi airport where he underwent five stitches over the left eyebrow and the doctor didn't allow him to travel as a result.
When i went to see him on being informed at 4 pm ai staff asked me to provide a date within the next 7 days for them to give another passage without any extra payment. I requested that since the doctor had advised the stitches be removed in 12 to 15 days' time to kindly consider his age and both my parents condition and give a passage after that date, that is in early december. The shift manager speaking through his juniors refused to give in. I left with my parents on the assurance that they are discussing the case and a remedy will be found.
It has been 9 days since then, and nothing has been done. I have been running from pillar to post to find a solution. I was told that i have to go to safdarjung airport to do the needful. On reaching there i was informed that i have to pay around rs 10, 000 more to match the current ticket rates!
Kindly tell me, how can one subject a non-pensioner 82 year old travelling with his wife suffering from dementia to this kind of gruelling stress and trauma when all he wanted was to be able to go to warmer climates to avoid the delhi cold?
If ai wanted him to travel with a bandaged head without recovering from the injury then they should have allowed him to travel on that same day! Who will be responsible if he had suffered a similar fate all over again just because a shift manager couldn't understand his medical condition?
Please address this urgently and revert. I would like ai to keep its word of providing him another passage at the earliest without him having to pay anything extra.