On comic 140 of book one, they had at least 5 thinkamancers unravel the three way link. But that link was for reactivating a volcano.http://www.erfworld.com/book-1-archive/?px=%2F140.jpg
I think a two-way link to make some banners carrying an emblem would not be as hard to unravel as one suited to making a volcano erupt, and Maggie might have had an easier time unraveling that by herself.
And considering that Wanda has at least some talent in all of the magics, even though her specialty is in croakamancy, she could have been on standby to help unravel a simple two-way link.
Hmm, wait... It wasn't a 3-way link with Ken, was it? Maybe Ken is super-loyal to Stanly?
On another note, about the decrypted units:
I've always considered a decrypted unit to be to the uncroaked, what a demon is to be to the undead.
The undead are generally mindless, malleable, and easily controlled.
A demon is generally a strong willed, traitorous, and self serving liar, and though can usually be controlled by the magics that summoned them in most universes, especially if it's a weak demon, I can't help but remembering a few stories where a very powerful demon breaks the bond that holds it or finds a mistake in a summoning circle meant to hold them, and almost instantly goes from being the slave to the master after finding that fatal mistake.
I am not sure if it's a stretch or not, but Decrypted Ansom apologized to Hamster initially, and was a bit of a suck up. But when Stanly talked to Hamster, referencing a conversation he had with Ansom, not everything Ansom had to say was positive. I'm thinking Ansom is trying to weasel himself into some sort of position for a power-play, and the weaker uncroaked are all going to follow him.
Also, if Wanda is to be believed, these "decrypted" units are the first ever created in Erfworld. I am thinking there is some sort of extreme unrealized disadvantage associated with them due to traitorous, self-serving intent, which would make the zero-cost upkeep that much less appealing. Maybe the units weren't revived at all, but were simply regenerated, and are now inhabited by some before-now unknown demonic spirit? Or an entirely new one is created for each unit, making them that much "different"?