NCEMI cancellation on Croma/tata neu

I plan to purchase a phone from Croma.
The phone comes with an 18 months no cost Emi which amounts to almost 7k in interest.
When I try to purchase the phone from FK/amazon then they reduce the interest upfront and I only have to pay 53k so I know NCEMI cancellation will work over there.
But I am planning to purchase it from Tata Neu as then I also end up earning neu coins even after NCEMI cancellation. The issue is that the interest amount isn't deducted upfront when purchasing from Croma/Tata neu. It rather shows up as cashback. 
So I am not sure if the NCEMI trick will work with it or not.
One person mentioned here (https://www.desidime.com/discussions/tata-neu-n...) that even though the customer care said that the interest amount will be credited in form of cashback after 90 days, what actually happened is that the principal amount was reduced (by the interest amount) when it was converted into an EMI and then the cancellation trick worked and he even ended up earning the neucoins. 

But that is only one person's experience. I want to know if anyone has experienced something different before I go ahead with placing the order.