Factual error: Tru arrives "more than three hours late" for the MCAT and then begins the test. Firstly, it would be pointless for her to even bother going at that time, since she'd have already missed the entire Verbal Reasoning section and possibly the Physical Sciences as well (depending on how much more than three hours she was late). Secondly, that's really a moot point since late arrivals to MCAT testing centers are not permitted to take the test.
Past Tense - S1-E4
Factual error: Davis tells Tru that glucagon is a substitute for insulin in diabetic emergencies. In actuality, it does exactly the opposite of insulin, raising glucose levels in the blood while insulin lowers them.
Factual error: Both Tru and Davis refer to the petechial hemorrhaging (i.e. the bleeding behind Paige's eye-lids) as 'petechial imaging' at least twice in the episode which is very shabby given their experience working in the morgue.
Factual error: This episode misrepresents the scheduling and format of the MCAT. The exam is given in four sections, with an hour lunch break between the second and third. The morning session lasts three hours and fifteen minutes, the afternoon two hours and fifty minutes. If Tru was "more than three hours late" (and, presumably, less than four hours late) when she arrived after 2:30pm, then it presents two problems. Firstly, the session should be in the midst of its lunch break. Secondly, the test started much later in the day than the real MCAT does.
Chosen answer: The next episode shows that Tru didn't meet Luc after all, even though she should have been in work by the time he showed up. I think the answer is that the writers don't actually know.
DavidK93