No need to open an SB account. You can open a digital FD directly with Ujjivan. Only the first time process involves vKYC. From there, it's a breeze. I am sure most other banks will have a similar system. If anything happens, we have RBI to rectify and get compensation as well. Just be sure not to put more than 5 lac in a single bank (any bank).
Disclaimer: I have FD with Ujjivan along with digital SB account (when I opened it, it was zero bal account, now min bal is 1k). My spouse has digital FD account without SB account. Both accounts are less than 1 year old, though.
Going directly with the bank gives a slightly better FD interest rate. Also, when dealing with any issues, it is easy to talk to the bank directly rather than through Stable Money, Super Money or any other platform.