I just made an attempt of eating there, the waitress clarified that Cross contamination can happen in the kitchen.
They have a separate allergy menu that lists gluten free items from their menu. I had the salted mackerel, sushi and the matcha panna cotta. Good food. No issues. They also provided gf soy sauce (I had to ask for it). I stayed away from some of the other sauces to be extra safe.
no gf list. has tamari soy sauce available in individual packets and a few dishes that are naturally gluten-free, but that's it.
Izakaya with gf soy sauce and a list of dishes that can be prepared gf. Need I say more?