That is a plausible hypothesis except for one small detail. A SPICE simulator is unlikely to have a specific model for a 74HC74. What it will have is a behavioral model for a D Flip-Flop. You then enter parameters so that it behaves like the part you are interested in.
What we have here is a kind of chicken and egg problem. You can't simulate the parts without enteing the parameters, and you can't enter the parameters without understanding the datasheet, and you can't get the simulation to match the datasheet without a pretty deep understanding of the real part and the simulation process.
This is really not the student's fault, it is the boneheaded sadist of an instructor who is too lazy to teach. A pox on all the lazy instructors in the world. If he was doing his job, his students would not have to come to us with their hats in their hands asking for help on rediculous assignments.