The Witch Hut and the Garden are both accessible for me on the latest Android release. I get the same [exception] when starting from Slo-Grow, but selecting [Ignore] on the bottom left allowed me to continue to the game.
I recently downloaded the Steam demo, and can confirm that the [Wishlist Mushroom Musume on Steam today!] banner is in the same place on PC that the Witch Hut is on mobile.