OK contact your VC. Here is what I would do for the future. I have been playing varius table top RPG's for 31 years. Have GM'd for 30 of those years almost exclusively. I would assign another GM and let him play for a while. If he does not want to play then find another player to round out your group. The only way to fix a "Bad GM" is to let him play under a good GM so he can learn. Keep in mind GM's do make mistakes. Many "Bad GM's can become great GM's if given the proper chance and training. Not everyone is meant to be a GM.
GM's must be good story tellers first and foremost. Missing plot que's and misinforming the PC's can be very detrimental to the group as a whole. Just remember though RPG's are not just hack and slash. You do have to RP to get information and solve puzzles. Some modules (not saying this one is one of those since I have not read or run it) intentionally misdirect the PC's if the right questions are not asked.