It should be Bret or Brett, who is Brett's fatter and found people for him through visualize to do several acts for the sect, and as Bret is the "father" of the whole organization, he doesn't need a tattoo. Even better, as he knew that these 3 had this tattoo, he painted a fake one for Heller to see to frame one of the 3 that had the tattoo. The thing that confirms this is that she said they were vertical, and these were horizontal. The tattoo is for people who join the sect. Gale, Thomas and Reede are just part of the people of the whole grid. Hell, even Teresa could be in