How to bake frozen breaded cod without breading sticking to alumnium foil?
One possible work around is to put a couple of chopsticks between the foil and the fish so that there is no direct contact with the foil, a cheap rack. Or you can roll up some extra foil into little rods to achieve the same.

Protein-laden water seeps out of the fish and makes a glue between the fish and the foil. By raising the fish, you get some air currents and the glue is kept away from the fish. Cooking from frozen exacerbates this because initially all the heat goes into the frozen water to melt it without raising the temperature of the fish above freezing point. There is little evaporation going on at such low temperature.