Cool idea! I think I got the Macguffium (it was the green bottle, right?)
I really like the atmosphere you set up. The color palette and music give this sense of urgent sleuthing. I think there's potential in the idea if you decide to build on it.
If you do decide to continue, here's just a few notes to consider:
Every time I tunneled it was in the direction I was walking. You could just make space do the tunneling. Or develop scenarios where the player has to walk one direction and then tunnel in another.
There are a lot of rooms to pass through and at some point I wasn't sure if I was making forward progress or back-tracking. Distinct landmarks every couple of rooms might help but I'm sure there are other ways you could solve that too.