Need help desperately

[LadyCM]

This phalenopsis was given to me by a dearest friend before he passed so it's a big responsibility. He didn't know much about orchids and planted it in a huge clay pot-no ventilation-. He used broken glass to fill part of the pot and the rest with dirt. Believe it or not, the plant grew, has about 3 other plants from the bottom and right now about 9 spikes. Problem: the roots are dying, the dirt smells bad and some leaves have gotten black spots. With so many spikes I don't know what to do. With so many plants growing there is no ventilation inside, there are about 6" from border to soil. I use a flashlight to take the roots pic, the white is a reflection.