I am hoping that even if you score 40% only on that mock exam you can still pass the real exam.
40% ?!?
I don't believe that scoring 40% on the HSFJ mock will give you a good probability of passing the real exam. A passing score on the exam is 62% (44 of 70 questions).
And the HSFJ mock is quite similar to the real exam. The major difference being that the real exam tells you how many multiple choice options to select, but the mock doesn't.
I don't know about you, but to me US$200 is a lot of money. When I took the exam I was 100% sure I would pass.