I meant to reply to this when it was first posted, but forgot.

As John says, for these kind of drives, there is no encoder feedback to the controller.
You simply send them the step/dir signals, and they handle the positioning.

Depending on the exact drives you have, I'd only connect the Alarm signal, as that should be triggered on a big position error, which would indicate a stall, by which point you'd want the machine to stop anyway.