First off, I am very impressed you decided to go with a 3D game for a game jam, on top of being a solo dev. You programmed, made the story, drew the characters and created the models all by yourself??? That is some insane work right there and you should be proud! Great job there! :D Also love the Persona-esc UI and the character portraits!
Like ζοιδ mentioned, I do feel the overall story and investigation are a bit straightforward, and there were elements of the dialogue that made me think I missed something (Like Bae having a picture of ______ in a dress). Also, with the members on the island, it was pretty easy to distinguish who was the culprit (I won't mention who for spoiler reasons, but when I checked the electric box and found ____, it was already tied to 2 people, and then you have her first reaction, I was 99% sure the culprit was ______). Also, the point-and-click movement mechanic did have some minor bugs, like the path finding being off in certain instances but that's very minor.
And again, this is extremely impressive for a single-person effort! If you can build off of the mechanics of the game and dedicate more time to the investigation, this can grow to be a great game!