Lack of infectious development (so long as you get any development at all) is indicative of either lack of sufite, too much sulfite, or lack of a restrainer, such as potassium bromide. Additionally, it takes developer usage to generate the semiquinones that produce infectious development, i.e., "old brown." Simple oxidation does not work here.

Try again with your original dilutions, but substitute a liter of your old developer for water. (Make sure your old developer is "dead," as often it still has some activity. Any lithable paper thrown in will accomplish this.) Add 5g sodium sulfite and 5 grams of potassium bromide. When you get a well-worked batch of old brown, usually don't even need the potassium bromide. Good luck.