I decided to give the blue shirt bleaching method a try as well. I ended up finding one on ebay, submitted an offer, and immediately after I found a second one at a lower price than the first one I submitted the offer for so I got two of the shirts.
So when I went to buy the dye, I saw the Rit Color Remover and bought a box of that to give it a try. Unfortunately 1 box isn't enough for "bleaching" and the outside label doesn't even tell you that. The inside of the box has the directions and tells you how many boxes to buy depending on your goal, but I digress. Here's the results after using 1 box of the color remover in the washer, left shirt is a dried original color, right shirt is still wet after the treatment.
I knew even after multiple treatments that wasn't going to cut it, so I started bleaching. After about two hours with slightly diluted bleach (maybe 50:50? maybe more water than that), and I added another blue cotton shirt as a control. The Salt Valley shirt is on the left.
After another 4 hours. I was getting ansy so I figured this was light enough. Still a bit pink and oddly the areas where the fabric is doubled up it still shows a bit blue.
And now with the Rit Pearl Gray dye. Agitated in the wash for about 45 minutes. So pink and gray end up making purple. I might try to rebleach it or redye it, not sure. It's definitely more purple than the pictures show. The colors on the collar and the cuffs seemed to have evened out enough.
So yea, I have fabric markers to color the embroidery blue and red. Still trying to decide if I want to try to recolor the entire shirt or just keep it as is. I might color the second one before proceeding with the first one.