What Causes Infection,loss Of Hearing And Drainage In Ear?

My husband had a cholesteatoma 14 years ago. Since then he has had chronic ear issues including infection, loss of hearing, drainage, etc. Recently he has developed a severly foul odor in this ear. His ENT insists that it is not an infection and that he needs to get it cleaned out more frequently but every time they clean the ear - he gets about a 48 hour window of relief before the smell comes back and within a week he will have pressure behind his ear. What could be going on?