I don't know where you got FirstNet equipment manufacturer from but their website indicates they make and sell headend broadcast equipment. So the stuff the CATV company has at their facility that takes the satellite feeds from various networks and sends it out over cable TV, that is what they say they make.
FirstNet is based on the ATT cellphone based network. It is not a separate internet but is a Government prioritized cellphone with phone/data/video/PTT.
Upon reflection, I would like to ad to my post. Their ad says they also sell Portable and mobile communications equipment. And my meaning was they were not making gear FOR AT&T, merely that maybe it was compatible on AT&T’s FirstNet, if that’s what they were advertising. I would like to ad it could very well be that the ad I refer to is for DMR equipment.
I refer to the bottom left hand side of their website, an ad that pictures portable and mobile As for Orbittechsatelite’s use of radio at their place of business, they could be using the cheap stuff you can get at Walmarts all the way up to expensive commercial gear in just about any band and mode.