This could be an issue with TRS spec on the device you are trying to communicate with.  

The world of TRS MIDI was once a wild place.  There are 2 ways to map MIDI connections via TRS and for awhile there were NO STANDARDS!  Basically half the companies where doing things with the "TRS A" Spec and half where doing "TRS B."  Eventually the MIDI association adopted the TRS A spec which is what the ZOIA uses.  
You can find more information and which spec your devices are using here - 

If your device is TRS B, you would need a TRS B to TRS A cable or you could make one yourself.

Maybe the easiest thing to do would be use the TRS A MIDI dongle that came with the ZOIA connected to the ZOIA side and then us a TRS B MIDI dongle with your TRS B product and a 5 pin MIDI cable between the 2 and you should have communication!