I did not see a link for the option that you were considering, but this might work for you. It is a bluetooth OBD scanner that works with an app on your phone (torquePro). A lot of folks said that it was hard to find the transimssion temp on Hondas in early years, but looks like the one below was successful. There are a lot of youtube guides on this topic, and it can be used only when towing (connecting device to obd port and then to phone or tablet). This is only a suggestion, and I can’t guarantee that it will work (test at your own risk) but definitely worth investigating.
Maybe some of the experienced off-roaders can chime in to see what they use.
Youtube search “transmission oil temperature torque app”
Odyssey forums, transmission oil temp