Devastating experience on the day of my GMAT exam- Please check ID

Dear all, since I learned a lot from this forum, it is time for me to give back so hopefully, nobody experiences the same thing as I did.

I am a Canadian permanent resident, and I thought I could get in with a driver's license or my other government IDs. I showed up at the center 1 hour earlier just to make sure I can be there on time, and they told me to come back 20 min to the exam. I told her I just want to check that everything is alright and she told me that I cannot get in without my passport, I called the GMAT service number and was on the phone for 1 hour 25 minutes (ridiculously slow service with not bright customer service). Basically, they told me it is a lost cause and I have to go home.

I called the GMAT center a few times more ( each time I was on the phone between 40 minutes and 1 hour 30 minutes, few times they hung up mid-conversation) and they finally decided that Permanent resident card is acceptable ( It is clearly written on their website that it should be acceptable). Please make sure that you have all the facts and check your ID requirement before entering the exam center. And if possible tell me how I can complain about the long waiting times and nonchalant behavior of the phone operators? I swear I got few different answers each time and each time you ask them a question they put you on hold for 30 minutes before answering a very simple question.