I have called and emailed Jack's Magic and they told me the "area support rep" would be in touch with me likely in the next 24 hours. Hopefully, he will have some thoughts on the best way to proceed.
I would suspect combining with zero alkalinity may be the best idea as the directions do say that when testing on a step, it may be beneficial to pour some additional acid on the spot prior to test.
Either way, I am planning to talk to the rep and see what is possible. The weather here is not hot yet so I have a little more play time to figure this out before the kids will demand the pool to be swimable. HAHA
Spoke with the Jack's Magic rep and he has advised me to keep the PH at 7.2 and apply 1.5 qts (for a 15K pool) to the water and brush frequently. He is currently planning on coming out to check out the progress next week and see what can be done from here. The current thinking is this will help loosen the stain and then another test may return a more obvious result.
I will say after 24 hours the stain appears a bit lighter and where I had applied stain test #2 appears is a white streak in the stain. So perhaps this is helping? In the meantime, I am planning to brush 2 to 3 times a day until he comes out and adding acid to keep in line as needed.