What causes eDSPermissionError when running dscl?
Its a good question. I honestly have no idea. Does Apple still support using NFS home directories?

The only thing I can think of is to mention that using sudo is not the same as executing a command with uid=0, gid=0. Necessarily. Anymore.

And this is particularly applicable within the context of Directory Services, I think (?),  because that's where you Enable Root User these days. So I might try enabling root in Directory Utility, and trying with a proper su root?