There is no fuse indicating "fridge" on the 12v dist panel in our 7355 power centre either. However, the "source" must be there, because the fridge works with no battery off the converter, or with no converter, it works off the battery.
It was posted that the fridge has its on circuit board fuse, so maybe that is why it doesn't have one on the dist panel?
So unless there is a shared fuse, not marked "also fridge" the fridge 12v wire must begin near the main lugs where both converter and battery wires meet. check the back of the positive battery wire lug on the DC dist panel. ISTR ours has two set screw holes that maybe one of them has an extra wire in it? Just guessing-- I haven't tried to find my fridge wire yet! :(