Well, it’s time for the chapter 5 class trial. My theories are still half-baked, but if I want to get it done today, I have to begin now, so I’ll just briefly write a short version of my thoughts here and proceed.
First off, since Monokuma said no rules are being broken, yet neither Kokichi nor Kaito appears to be attending the class trial, I will assume both dead as the rules state all surviving students must participate in the class trials. Both corpses are in the hydraulic press. This leads me to two main theories.
First, the Maki culprit theory. The crossbow wounds suggest that a third party with a crossbow was involved in the case, as it seems highly unlikely Kaito and Kokichi would’ve shot each other dead with the crossbows and then somehow ended up crushing themselves in the hydraulic press. Unless Kaito taught someone else to assemble the crossbows, Maki is the only possible culprit in this scenario. The way I envisioned this happening is Maki and Kaito agreeing on killing Kokichi with crossbows, Kaito shooting at him inside the toilet and Maki shooting at him through the window. After Kokichi died, Kaito gave Maki the hangar alarm remote through the window, and Maki shot him in the arm as he did so. The lethality of the arrows was improved with the use of poison.
Then, Maki simply went inside, crushed both corpses with the hydraulic press, and left. However, this leaves a number of issues unanswered. Why was there a bottle of possibly poison in the toilet? If Maki used it, why not dispose of it? Who drove the Exisal into the hangar? It is possible Maki entered the hangar with the Exisal, I suppose, though I like the idea of shooting through the window. Why was Himiko the one Keebo saw bring a crossbow bag to Kaito? In any case, ever since I realized the localization kept the nickname Harumaki as the somewhat clunky Maki Roll, I’ve suspected Maki will be executed and turned into a comestible like Mondo became delicious butter.
The culprit could be someone else, such as Himiko, if we assume Kaito taught them to use the crossbow, but that doesn’t seem as likely to me.
Anyhow… the second theory is more Chapter 5 -like. Yes indeed, it is the suicide theory. An electrobomb disabled the safety sensor of the hydraulic press, and either Kaito or Kokichi crushed himself with it, along with his victim’s corpse. As twisted as it may be, I consider Kaito the more probable culprit. Kaito could’ve surprised Kokichi with the crossbow he got from Himiko, and then shot himself in the arm to frame himself as the victim. With Kokichi, the crossbow holes in the coats are less easy to explain, as it would require a lot of screwing around with the coats with a crossbow that he found by coincidence, all to confuse the investigation which would be plenty confusing already.
A number of the same issues from the Maki theory linger in this one, along with one major extra problem. The various pieces of evidence such as the arrows and the bottle of poison just being left there in the toilet could be explained by the culprit being unable to dispose of them any better since he’d be extraordinarily dead. However, there’s the issue of the Exisal, again. I suppose some random could’ve just driven it inside, finding the scene of crime in the process, but keeping quiet about it. Alternatively, the Exisal driving could have happened before the crime happened, and Kokichi would’ve just let them leave, I guess? Strange. One would think if someone barged in with an Exisal, they’d do so to kill Kokichi.
However, the main issue is of course the power cord of the hydraulic press being cut. I suppose it would not be completely impossible to arrange it to happen posthumously, but I can’t see any evidence suggesting this was the case. It could theoretically have been an accident, with the Exisal cutting it by coincidence when someone drove it into the hangar. That, or someone was in in Kaito’s suicide plan and agreed they’d cut the wire after the deed was done. Perhaps this hypothetical accomplice could’ve been the one who drove in with the Exisal, for this very purpose.
In any case, those two theories are the best I’ve got for now, and I really want to play through the class trial today, so I’ll leave it at that. However, a thing I want to point out is that the blood on the label in the poison bottle seems to highly deliberately conceal everything except the word “poison”, suggesting the appearance of the label is meant to mislead the investigation. Perhaps the bottle is not a bottle of poison, but a bottle of antidote, with the label reading something like “antidote for X poison”? However, I couldn’t think of any way to tie that possibility into any theory about the murder.
Time to find if I hit the mark with anything. My theories leave some things unexplained to an uncomfortable degree, but I still feel pretty optimistic.