Ah, the classic human bait scenario - usually that was Marian's job. But if the Sheriff already had Marian, and if he was working with Gisborne, then capturing the Sheriff would only put her in more danger.
Also, last time they'd killed the Sheriff he and Will had pulled the bait and ambush trick, so he'd be more on guard if they did it again. Not that he was about to mention that here, at work. Best to stick to finding the prison.
"Not really," he said. "We have the blueprints, but there's nothing about a location on any of them. We've had a look at his accounts but there weren't any clues there either. I reckon we've got to track him... wait outside the only address we have for him till we see him and then follow him... Rob'd be great at that, his disguises..." Much trailed off, the Rob problem rearing his head, but he tried to rein it in and stay on track. One dire issue at a time. "Waiting takes time though and if he doesn't go back to that house for days, weeks... then we've wasted all that time when we could have been doing something else."