Have you guys considered NDI? Bird Dog make really cheap full bandwidth NDI HDMI encoders which you can view on a laptop, iPad or phone. NDI HX is easier to pass over WiFi, and encoders are available from a bunch of companies like Kiloview. It’s definitely not the neatest solution, but because its just regular IP you can use specialised point to point APs from Ubiquiti, cable if its available (which can be helpful when you’re inside a building). It is also point to multipoint so there is no real limit on how many receivers you can use. You obviously still have the issue that you’re in the WiFi band, but at least you have the choice of channels with the Ubiquiti gear, and can even upgrade to WiFi6.