Mission Report: Land Invasion of the Islands

"You've told this story many times I'm sure, Bishop, but tell it again for the Council please."
"Yes ma'am. Two months ago, three spies were dispatched to the islands. One integrated into their Dwarven defenses, and the other two into their nobility."
"Did they face any troubles?"
"Disguising themselves as fleeing nobles from the Tsayids was trivial. The Dwarven one was more difficult as they have paperwork proving their bloodlines and familial names, but were quickly fabricated."
"And what did they report back?"
"They did not. None of them returned or ever filled a monthly report. We responded by sending a 'rescue' team."
"Why the emphasis on 'rescue'?"
"In truth, Councilors, the platoon of 80 men deployed were ne're-do-wells, malcontents, duty-shirkers, those with disfigurements or showed signs of lacking sufficient faith."
"Ah, a suicide mission! Clever. And what did their deaths tell us of their defenses? Artillery? Underwater mines? Witchcraft?"
"Uh.... no ma'am. They.... all survived."
".... If they lived.... then why are you giving the report and not their commanding officer?"
"When they landed on the beach, ma'am, some fat fucking Baron offered them food- and every single one of them defected. We now suspect the spies did the same."
"....This is an.... unusual outcome. What do you advise, Bishop?"
"Firstly, that the men are warned that desertion will be punished more harshly than any crime imaginable. Secondly, that only the most loyal shock-troopers are deployed to Spiritsglade..... and make sure they arrive well fed."