Unfortunately, I don't have much advice-just insight to the whole process. My experience has been that permanent marker is permanent on fabrics once it is absorbed into the fabric (which is immediate)--even when using bleach to remvoe it.
I am guessing the reason is because whatever the marker pigment is made of, it does not chemically react with bleach, which would remove it (the removal of certain stains is the result of a chemical reaction with the oxygen or chlorine bleach).
However, when we accidentally wrote on a non-absorbent surface, whiteboard,with permanent marker, we were able to use acetone (ingredient in nail polish remover) to clean up the whiteboard. Here it may be that the particles of the dried marker are washed off/removed onto the cloth, not reacted with. So this might work on other non-absorptive surfaces, just be careful that there is no paint under the marker because that might be removed too!!!
Norma