Ibibo Group / Goibibo — shedding responsibilities

This is to inform that, i had booked a round trip for my younger brother, from geneva to kolkata and return on a single booking id from goibibo, for travel starting 22/06/2018.
But it so happened that his first flight of the itinerary got delayed, due to which all his connections were unable to be taken, and there was one connection which was of a domestic sector. When informed goibibo of the same, they first acted that there are no delays and the passenger will be able to catch the flights as per the itinerary, but when explained over and over again, they released and then just shed their responsibilities, and just asked to get the domestic ticket cancelled and book a new ticket on our expense.
I fail to understand that when i have booked the entire itinerary with goibibo under a single booking id, as per the connections showing on their website, sill why such different attitude, when a flight has got delayed/cancelled.
It should be goibibo's responsibility to get me a change of ticket as per the new itinerary which has formed due to the late arrival of a connecting flight.
But, no, they just dint pay any heed, but were quick enough to send a mail with all the cancellation charges, which were then committed to be reversed through a request raised by them, the mail which cannot be send to the customer.
I seek the entire refund of the cancelled ticket, the price of which was rs. 6000/- approx, and also the amount which i had to further invest to buy a ticket on the counter for rs. 6050/- of jet airways, that also made through goibibo.

Original itinerary booking id: gomupkgint[protected]

New ticket purchased : pnr: 9w/oqpobx