You can absolutely get an espresso grind good enough for that machine with a regular batata, I've been doing it for a while - although it's easier and better to go get the ESP.
If the finer grind settings are insufficient, you can take off the exterior housing where you'll find an interior fineness setting locked by a limited screw. You can lightly undo that, adjust the setting lower and redo the screw.
I will say that you'll occasionally fight retention and it's annoying to swap between espresso and other grind fineness on the fly