I don't know the names of all of them

Dialog:

Man 1: You don't remember him?

Man 2: My company has a lot of employees. I don't know the names of all of them.

Is the bold-faced sentence perfectly correct and natural here?

Did your read this dialogue somewhere? If so please tell us the source and author.

5jj said:

Did your read this dialogue somewhere? If so please tell us the source and author.

Click to expand...

Sorry. I wrote it myself.

It's fine.

I'd use "I don't know all their names" but yours isn't wrong.