Yes - he is passing parasites and he will pass more of them before the cleanse is over. He may even pass a few after the 30 days.
The parasites are probably to blame for his symptoms and I think you will be surprised at how much better he will feel when he is clean.
After this 30 day cleanse - he needs to wait for 90 days before he can do another cleanse. This is to keep his parasites from becoming resistant. During the 90 day wait - he can eat foods that include the following herbs:garlic, onion, sage, thyme, cloves, ginger and cinnamon. Simply mix the savory herbs together in equal amounts and the sweet herbs together in equal amounts. Add a tiny bit of the sweet mix to applesauce or yogurt and such. Add a tiny bit of the savories to chicken, potatoes or rice. These 7 herbs will help keep him clean until he can do another full-fledged cleanse :)