You may want to go back and read the 2 posts 'how to set your bow's tiller' and 'don't stop at walk back'. I read these posts and had my one cam Martin Cheetah set up and BH tuned in about 1/2 an hour. Maybe I just got lucky but my fixed blade BHs and field points hit same POI out to 40 yds.
If you think you're doing everything correctly I would suspect fletching contact also. I went through the same thing with a Martin Bengal that I could not get tuned so I know your frustration. I ended up taking that bow back and getting a Firecat.