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I discovered by accident that you can take Ike's "Durlag's Tower tour" after completing the tower and defeating the DK. You can still travel to the tower, meet up with him on the bridge, and get the spiel. Despite clearing the room of traps long ago, a tourist still gets torched.
Then, when the DK should show up, Ike gives his "OMG WHAT IS THAT!!1!" line and forever freezes. Obviously, being dead, the DK can't show up, so there you have it. Ike is now wandering around with a couple of tourists for the rest of their lives in the tower.
I figured it fits, now that the place is cleared of anything hazardous, so I left it, but it feels like a bug.