Screw Terminal Broken Screw Removal
My answer is assuming the screws are completely removable from the DAQ. 

I would remove the screw using a left hand drill bit. Find one that is safely smaller than the threaded hole so you don't damage the threads, set the drill to reverse, and drill down the head of the screw. One of two things will then happen:


You will completely destroy the screw turning it to dust.
The screw will catch and become unscrewed since the bit is spinning in the reverse direction. 


Either way, go slowly and carefully so you don't damage anything else.

When the screw is out, remove another undamaged screw and take it to a hardware store or a place like Fastenal and they should be able to find a replacement for you.