I laid them on a towel outside to dry and a few hours later, brought them in to take some photos.
That's when I noticed.
I have never had a problem with color fastness in embroidery floss!
I have them soaking again in Oxy-clean and hoping they will be salvageable, but my joy at completing the project has deflated. I am glad that they are a quick project and not something that I spent many hours on (maybe 3 or 4 hours total). And the blank garments are not expensive. But still....