Hi Eric,
I am sorry to hear that! Based on my experience, the scenario description and wording of the PMPrepCast Exam Simulator are very close to those in the exam. I also tried to answer questions from other providers for the very same reason you mentioned: I didn't want to get "too used" to that wording; and - while performing consistently good on the PMPrepCast - some of the questions from other free sources I had no clue what they were asking... That made me anxious too, but to be honest I judged some of them quite poorly described, and no explanations was provided for the correct answer as well as for the wrong ones! To me this was an invaluable learning opportunity, because while you may understand why an option is correct, an explanation about why another option is not correct may be even more convincing - as you know that you may have different reasonable options, one of them being slightly better than the others. And that's the one you want to pick!
So, I believe it could be useful to try to practice questions from different providers, but don't take it too bad if you don't perform equally well.
Good luck on your exam!
Gabriella