I'm going to take a different route than the other answers, all of which (to me) appear to be encouraging the GM to use his 'guide' to actively screw with the players. I'm going to suggest right out of the gate that this is bad, primarily because the GM gave you a guide in the first place, so making the guide actively hinder the players is just underhanded, especially after he encouraged the group to make use of said guide. It's not the players' fault that they're making use of a resource he's provided.
Following that train of thought, I think the problem here is minimal, if non-existent. Observe; the NPC knows the region better than you do, and yet you think it's a problem that you're asking him about the best ways to travel through the region. This is precisely the function of a guide!
Now, the problem may very well be that the players are expecting the guide to do all of their thinking for them, and this is where the limits of the guide's knowledge should come into play. For example, if the guide is not a tactician, then asking him how to fight all the battles that may crop up during the journey is going to be unreasonable. Also, since no one person knows everything, having the guide simply not know the answer is also a valid thing.
However, these are all things the Gamemaster must do, and it doesn't seem clear that the GM is the one asking for advice. Rather, it looks like you as a player think that the group has dug themselves into a hole and may be blaming the GM for handing them the shovel. To that, I kinda have to say - nobody forced you to start digging. If you don't want to rely on the NPC for help... don't ask the NPC for help. Simple as that.
It may be a good idea, though, in the future for the GM to not provide an NPC that fulfills this role now that he's noticed this tendency among the group, but again, that's for him to decide and not you.