Yes.
What's your CC limit?
Few things to keep in mind thought :
If they really think customers received extra cashback / Kiwis then they can always take back the difference cb amount later on.
Ex~ In BBD or Prime Day sales I almost always buy things using my SBI SimplyClick credit card they give 10% instant discount & RP simultaneously. But after few months they always deduct those extra RP if they can't find any RP in your ac then they include that ₹ in the bill(this happened with me).
But here all the payments in your case is "In House" so no harm trying.
BTW I have few questions ~
1. I've heard that for a single RuPay UPI transaction is over 2k then merchant needs to pay a small fee when the amount gets settled, is this true? Can you check the settled amount in your merchant app? Please check & reply.
2. Please tell me the name of the merchant account provider. Like phonepe / gpay / Paytm or else...
Was about to ask you....