This ties in with the absentee warden theory, Fortier may not have been to the island in decades, and Alfred was working to long established protocols.
If he hadn’t visited for decades this would have made it more difficult for Peabody to identify the Warden, especially if Cowl is Nameless. There is a way through Winter to Demonreach used by the Gatekeeper and Maeve (Mab didn’t trust Harry appearing suddenly on the island and she can teleport). Kemmler still held the Wardenship when died (finally?) in 1961 allowing a new Warden to take it on, one of the Senior Council so Fortier did the ritual and never went back, all before Nameless went into Winter leaving Nameless frustrated not knowing who the new Warden is and subject to Winter Law. Nameless partnered with Kemmler and that connection would explain Nameless knowing about the Warden, the ritual, and about Demonreach’s defences (the latter he was in a position to pass onto Maeve).
Nameless original purpose in seeking asylum in Winter may have originally been to get access to Demonreach which makes me wonder - did he sell out Kemmler to the White Council to get a new Warden appointed, one who Mab wouldn’t block in the NeverNever? Did Nameless have Justin as a sleeper agent with instructions to recover Bob and The Word? We know Peabody was a sleeper agent, and if my theory was correct he was inking the Senior Council to identify and then kill the current Warden. Peabody was the Plan B.
The plot to undermine Winter through Nemesis would have come along later.
Fortier was one of the Senior Council who voted against Harry, did he suspect DuMorne, and this was why DuMorne retired from the Wardens after Kemmler and was worried about Harry’s connection to him? Was that the reason he was absent from Demonreach (or one of them)? Nameless association with Kemmler was known, so Fortier would have known this, and was worried about Nameless being in Winter and refused to use the Winter Short-cut? This actually paints Fortier in a much better light, his distrust of Harry then makes sense, he might have concluded Harry was being prepared as a weapon to assassinate him to free the Wardenship. Was Justin mind-controlling Elaine and then Harry to get them inside the White Council as apprentices under his control in the same way that occurred with the Captain?