I'm beginning to believe you should be very careful about building up the rest of the bike, as you don't seem to be digesting information very well. After asking for advice it took you quite a while to accept and understand what to check to see what the problem was.

Now you say you are lead to "believe" it is the frame, but your picture clearly shows you have a string run that would allow you to easily confirm that "belief." One problem, though - the strings are tied to the seat stays, not the dropouts - as both my earlier instructions and Sheldon's specify (although I would note that the illustration on Sheldon's site incorrectly shows the one side tied to the top of the dropout braze-on). On top of it the strings are at different heights on each stay, which guarantees an inaccurate measurement.

At least you are having someone competent correct it, though there's no need to "sort it out," as it's very straightforward to track a rear triangle.

p.s. Are you sure your tire is pointed in the right direction?