Don't connect the two 50 pins from the DAQboards together, because this means you will connect +5V, digital and analog outputs. Sure there will be no surviving boards.
I would just tap the signals you need from the pressure sensor, I guess two analog inputs (differential) and a ground-signal and route them to a screw-terminal box that is available for your 50 pin cable. Such a box is always handy for quick but firm connections and measurements.