Sensors not appearing in Node-Red but discoverable in Alpha station

We are trying to deploy 40 sensors in a demanding maritime environment (thing multiple steel decks and bulkheads). On one of the decks we have 4 sensors and we freshly installed an ethernet modem nearby in order to collect the data. We run Node-Red on windows 10. The modem has been in place for a couple of weeks but no signals are received (we use default PANID on all modems and sensors for simplicity’s sake).

Yesterday I accessed the modem via Alpha Station and could see the sensors transmitting data while at the same time I couldn’t see them connected in Node-Red.

Any suggestions?