Is the quilt top square?
If, yes, then we can find a solution.
That would be much easier.
But I didn't know if the length was 50" or 70". So that matters if you might add "coping" strips to make the borders fit.
I'm guessing you're not working directly from a pattern - more from the picture. So if a border had to be a bit smaller or larger, you don't really care, right?
(which is really the way I like to do it myself ;-) )
And I get NOW why you wanted the 5" 9patches.
Also, ooc, are the 9 patches a mix of the braid fabrics and the white, or are they all scrappy braid fabrics?