Desert moles, being mammals, excrete nitrogenous waste in the form of urea.
What is Urea ?
In comparison to ammonia, urea is comparatively less poisonous and facilitates effective nitrogen excretion while requiring less water.
Mammals have developed the capacity to change harmful ammonia produced during the breakdown of proteins into urea in the liver. This includes desert moles.
Therefore, Desert moles, being mammals, excrete nitrogenous waste in the form of urea.