According to the FAQ page, you can use Prepaid Cards to buy Gift Cards.
#Am I able to buy the 2-month membership Gift card with a prepaid card?
spark pine
spark pine
As it's like a pre paid card, and the FAQ that I linked above says that you can use pre paid cards to buy GFN Gift Cards... I think that you shouldn't face issues to use it.
BUT... To make sure, contact NVIDIA Support and ask them directly:
https://www.nvidia.com/en-us/support/consumer/
Scroll the page down, and you will find the Live Chat and Ask us a Question links.