this was so much more engaging than i expected-- gonna echo another commenter here to note that it took me 6-8 hours to get through the game & i only got frustratingly stuck once. the mystery is designed very well.
i think you've also tapped into something special with how the interfaces & the researching behavior interact. you've essentially split up the functions of a text parser game across a couple different tabs, sort of forcing the player to move between these tabs & actually earnestly learn & retain fictional information. it's very Sam Barlowe, 90s-00s narrative design-y. it's also very true to how one does research. as someone who does a lot of historical research with often fairly inconclusive findings, it was super satisfying to use those same behaviors make demonstrable process through a system.
The Roottrees are Dead is a great work. thanks for sharing it.