Travel Triangle - Travel Triangle forcing us to accept low balled offer from a hostile vendor for covid 19 reschedule

My wife and I booked an Iceland trip for April **** with Travel Triangle. Twilight Escapades, vendor from Travel Triangle pushed us to reschedule the trip claiming that even though they are unable to conduct the trip due to cancellation on flights, their vendors will not refund us any money if we delay in rescheduling the trip.
Even after back & forth email communication as well as phone calls, we haven't received our pending refund from TT as well as agent who handled our Iceland booking, rather we are being given a credit voucher to be used within Dec **** for the amount of Rs ****** and the agent wants us to pay double the amount (Rs *.* Lakhs ) for a trip which would cost equal & sufficient with the credit note which they had given to us.
Travel Triangle claims that they have no responsibility here and is trying to close our ticket saying so and leaving us with a credit note, and a vendor who had been extremely rude to us.
Twilight Escapades had been very hostile and they even told me not to talk / reply in emails since my wife is the one who booked ! Also, they even claimed in email that our calculations are of no value and we should just go with whatever they say since they are the business. (Please find screenshots and evidences for these).
I have absolutely no trust on the vendor any more and with Travel Triangle saying they are not liable, I am left with a vendor who holds my money and doesn't seem to be accountable for the same. Please help us.