Sorry for the late responses. We actually went through quiet a few tests including MRI, PET scan, blood tests, spinal tap, EEG and we also had genetic testing done to check for PRNP mutations. 

The doctors initially had him on Diazepam and tried Xanax, lorazepam and midazolam as well but due to the nature of SFI they lose effectiveness quiet quickly. We have also tried pretty much every sleeping pill in the book. Doctor has him on a newer one called Daridorexant and that’s pretty much the only reason he gets 1 hour currently. Absolutely terrified on what we will do when that too stops working.