Seems like with AT&T the Borons are expensive paper weights. I have 10 of them that are of no use because they don't seem to work with external AT&T sims. I have tested and tried everything imaginable for around 2 months and have given up on trying to get them to work with external AT&T sims. Good luck, let me know if you can figure anything out.
Also, worth noting. 1 of the Borons did work for some reason, though the same procedure and code on any other device will not work. Not sure if it's faulty harware or what at this point