You need the Frontier account for your commander save (all your CMDR progress stats * are in Frontiers servers, not PSN).
The account requires first name, last name, and email address only, from memory. So long as it's a valid email, you can put whatever you like for first and last name.
If you are worried about it, you only need to enter a credit card, if you are buying from the store, and you won't be doing that on the PS4, that'll be all through the PlayStation Store, I would imagine. (I'd like to think that Frontier would offer a Lifetime Expansion Pass for the PS4, but I reckon Sony won't like that - at least if I ever move back to playing on the PC, my LEP on that platform will still be valid.)
* and I believe the log of everything your commander has done, so if you lose your ship to a bug, Frontier can confirm what you were doing at the time, etc , for working out the nature of the bug