Answer

The Attero Tech by QSC unD4O is a Dante output device utilizing the Audinate UltimoX card. While the device can output four channels of audio from the Dante network, it is limited to two Dante flows. 

As any subscribing device creates at least one flow on connection, this limits the unD4O to receive from two sources and up to four audio channels. 

Sending four MXA910 microphones to the unD4O requires either DSP or some other capable source to first combine the channels to one or two Dante flows.