I definitely did look at the Strategy guide; it's the first place I always look and went to the area you refer to; surprised and disappointed that it covers everything but the Secret Room.
Your link to BFG is also familiar. In each room you play aHOG and receive a silhouette picture of a famous sleuth. That discussion focuses on those pictures and what gets done them, not something I was having any problem with. I did post my question asking for help to solve that one hog scene and, nso far no answers.
I also checked the WTs from BFG and Gamezebo. Neither of them talk about the hogs in the secret room, only dealng with the pictures.
Every so often I go back and try to figure it out or just press the numbers hoping to hit the answer randomly but so far no luck.