Hi from experience Cahill has actually not helped so much. Maybe his age has something to do with it but it seems if he cant find something with his scrape test he doesn't go much farther than ordering a few blood tests.
Also his test missed protozoa that another lab claimed to find months later and a blood test also showed amoeba at the same time.
Now just recently I gave his office another try- his test didn't find anything though it's possible parasites drugs contributed to that and an amoeba blood test came up negative so he left a message saying to give it time and he found no evidence of an active infection - though many on here may be able to attest tor regular blood tests showing them.
There is a Dr. In St Louis - Simon Yu that does lengthy medicine protocols for parasites and has a test for them that tests around the body to see what is working and not. Not sure it shows exactly what parasites you have but may give clues. At least he recognizes the issue and tried to work with it.