Probably. Most of the people at the clinic I went to did not have ME/CFS. There were 3 or 4 I could see it in ... most were nicely dressed and with make-up, bored and fidgeting, bouncing babies on their laps, etc, in the waiting room.
The clinic I was at (not Nijmegen) also kicks patients out after 12 months, according to the contract, though sometimes might extend the "treatment" to 18 months for an additional fee. In my case, the travel, "relaxation" therapy, and stair climbing to get to offices was making me crash, so I cancelled my future appointments. They retaliated by removing their diagnosis of me having CFS, and replaced it with a diagnosis of being overweight
I wouldn't trust a single thing coming out of a Dutch fatigue clinic, except the horror stories coming from patients!