I can’t comment on Isotherm fridges I don’t have one. What I can say is that on my Classic 35 the switch at the switch panel operates a relay behind the switch panel. I presume this is to avoid a lot of current going through the switch and exceed the switch rating. From the sounds of it your 34P is wired the same way. And Yes live power to the fridge all the time is a bit unnerving.
The membership association for owners of Dufour Yachts