So, running some math through, and I don't see how that recipe goes from 9gal at 1.044 to 6.75 gal at 1.062. I calculate 1.059 @ 6.75 gal, and 1.061 @ 6.5 gal.
I do believe that the refractometer underestimates the gravity at higher temperatures, but can't be sure.
When I do it, I just note the numbers, and don't worry too much if my gravity is off by a point or two.
If you want to know for sure, you need to be really exact with your volumes. If you measured the volume (6.5gal) at 150*, you would end up with about a 2-2.5% difference in volume (due to contraction).
I think you are doing fine, but joining a club will certainly allow you to find someone who can critique your processes, and it is also great to see how others brew their beer.