On my first camper I tried to solve this problem. It's a design issue on refrigerators that have a manually lit pilot, and nothing to do with dirty orifices (although that might aggravate the problem). The design problem is getting a proper airflow through the cooling coils and to enable combustion, without having so much airflow the pilot blows out. I tried putting a furnace filter over the access cover, taping the lower third of the cover, and putting a wind baffle in front of the chimney cap on the roof. All these things helped somewhat. The roof baffle helped the most. But I could always find a situation that caused it to blow out - traveling a bit faster than usual, bad cross wind, passing trucks speeding in the opposite direction. In the end, I ran it on 12V while driving.
I now have a more modern designed fridge that ignites on it's own (no manual lit pilot required). I'm sure it blows out occasionally going down the road, but re-lights as required. Things are certainly still cold / frozen when I get to camp. I suspect you'll come to the same conclusion - 12V, or a new self-lighting unit.
