So I'm in the KoT's castle, trying to get the criminal record. I figured out how to use the plunger to get up into the vent. After that, I'm stuck. All I can do is tiptoe back and forth up there, but the game won't let me jump down -- neither back the way I came nor down into the Record Room. I've tried using everything in my inventory, to no avail. SB informs me that stealth is required, and the KoT keeps babbling on about cake. No help.
*any and all spoilers, however bloody obvious, are wiggidy-wiggidy-welcome.