You don't need to open a current account to get a card. These are just sad tactics that some branches do to have a high CASA. If the credit card guy is competent and is not bound to branch tactics one can easily get the card.
BizBlack is a decent business card but on diners platform so acceptable could also be an issue.
- If you do not have HDFC savings/current account, you still can get the card. Just go to a nearest HDFC branch and ask for BizBlack. Assuming credit card guys are competent at the branch, you will get the card without account. Its just that some branches do these tactics that bank do not give card without account. They spread their misinformation and ignorance to the world.
- If you already have HDFC savings account, you still can get BizBlack. Ask your RM (if you have), or your BM.
- If these things fails, maybe just send an email to HDFC PriorityRedressal.CreditCards@hdfcbank.com asking for the card making a case using your spends which are quite good for their waiver criteria.
A wild idea to utilise AmEx in places where it is not accepted would be through wallet load.
That amount could be used either to create a mandate or maybe if app gives prepaid card to setup the recurring payment.
I am not sure if this is even possible and thus... wild idea