What does this monster know?

Here's a go at something I've wrestled with forever.

Monster's Dungeon Knowledge

Roll	Hostile	Neutral	Friendly
2 or less	Walks into nearest trap	Wanders randomly for d6 turns	Moves in circle 2d6 turns
3-5	Nearest hostile lair	Nearest stairs, etc.	Nearest potential ally
6-8	Leads into nearest trap	Nearest dungeon menace	Nearest secret door
9-11	Nearest monster allies	Nearest safe room	Nearest trap
12 or more	Nearest enemy of monster	Nearest big treasure	Nearest unguarded treasure

Modifiers: Leader or significant NPC +1, Smart +1, Cannon fodder -1, Stupid -1

The party may be searching for something specific.  If it is on the chart and either above and/or to the left of the chart, the informant can help, but with a chance of misinformation equal to 1 in 20 for each step away from the result.  Double the chance if the informant is Stupid.

If misinformation occurs, treat result as if the original roll had been 2 or less.

Example: The PCs meet a sphinx and obtain a Friendly reaction roll.  The net roll for Dungeon Knowledge is a 12, so the sphinx could lead her new friends to the nearest unguarded treasure.  However, the party is desperate to exit the dungeon, so they specifically ask her about stairs or other conveyances up.  "Nearest stairs, etc." is 3 up and 1 to the left from the indicated result, so the chance of misinformation is 4 in 20.  Of course, since this is a sphinx, misinformation is probably the result of her talking in riddles.

Q: Why doesn't the average monster know as much about their immediate environ as most people know about their neighborhood?
A: Because this is a game and letting one dumb kobold ruin all the surprises in the level is no fun.