Thanks for the comment!
Being unable to use your PS4 controller is unfortunate, and unexpected. We tested the game with PS4 controllers, and a hodgepodge of random controllers. Aside from some bugs with the camera the PS4 controllers seemed to work properly. On my PS4-ish gameStop brand controller in godot the start / select buttons are mapped to the middle joystick buttons. And another offbrand PS4 had the start/ select buttons mapped to the triggers. Perhaps its something similar.