That's good to hear. But I have to say that it might still take some years. I will start from scratch and will have to learn c# and unity while making this game. And there are many complicated little mechanics that are not so obvious for the player like the culling-system.
If there were good chances that I could solve this bug with less than 20 hours of work I would do it because I am not sure if the bug is limited to that room. I think it can appear in all rooms of the watertemple that are accessible with the submarine.