I could see requiring a certain number of psychological/psychiatric visits prior to diagnosis. It took them a year to diagnose me and 5 years to diagnose my fiance, so I guess I'm not really familiar with the concept of walk in, get diagnosis, walk out. In fact, the clinic I go to does a preliminary diagnosis on intake and you get your official diagnosis after 6 months of treatment, so I don't see that as unreasonable.
But institutionalized might be a big stretch and sleep tests might be a bit much. I can't sleep anywhere but my own bed (otherwise, I'd love to do a sleep study - I've been an insomniac my whole life) and, like others have said, I can't drop my life for 2 weeks - I have another sufferer to take care of (who is taking care of his disabled dad and grandad).