I have just asked my client to ask one of his colleagues who has filed if they were able to file electronically and pay just income tax and Medicare tax.  I have a feeling they are going to find that their preparer subjected it to SS tax as well.

That is a very good point about just paying the employee share of the Medicare tax.  I can accomplish that on Form 4137 but since it is not tips and I would then somehow have to negate the 1099NEC, I am not ready to go that route.

I think a novel size explanation attached to the return of all these moving parts might be in my future.