Interestingly enough, all of the formulas I know of that used Cadmium used it for contrast control. All of the formulas I know that required warm tones used Cupric salts, Mercury salts or Lead salts and some used ammonium salts. Also, in addition to the above salts, most warm tone papers used a different addition method such as Azo warm tone. So, it is interesting that everyone seems to link Cd salts to warm tone when I have never seen it done so in acutal practice.
Cadmium was replaced by a set of non-toxic organic chemicals in the 60s and yet EK still produced a line of warm tone papers.
I have also found that some warm tone papers were exactly that. The emulsion was the same as a cold tone product, but the paper used for coating support had been lightly tinted with a brownish pigment or dye.