Starring: Taiki Matsuno, Masashi Tamaki
The Death March of Young Kindaichi File 2 - S2-E2
Plot hole: It's unreasonable, nor is explained in the denouement at the end of this arc, how did the murderer, who stayed behind everyone else on purpose, get to Shinomiya who was ahead of everyone, went inside the cave before everyone else and didn't have a reason to hide, cooperate with him or anything of the sort.
Inspector Kenmochi the Murderer File 3 - S1-E21
Audio problem: Kindaichi is listening to the recording of the phone call a couple times over; however he does not listen to it in a loop, but rather the file shows up as lasting 52 seconds, with the call being just a handful of seconds. On top of that, when he listens to it again in front of the building, the timestamps don't match.