Yes, HDFC provides points on NPS payment. I have checked on both DCB and Infinia. (Last checked on 3rd April).
There are ~1% transaction charges on CC payment but we do get 3.3% from HDFC. Hence, savings of 2.3%.
I pays though Billdesk payment gateway every time. I have heard SBI payment gateway doesn't accept Diners cards.

Best way to check is by paying small amount by HDFC card in the multiple of 150 and after few days paying the rest amount. I follow this every time since I fear HDFC may stop providing points on NPS anytime.