I'm pretty sure the main cause will be boredem in this case if he has chews. Try making a play pen or securing a room for floortime! They will really appreciate a huge space to wear some excess energy off. If you already do this then either do it more often (i try to do it at least 3 times a week, then put in running ball and run around on my bed and sofa on days i don't).
Or make it more excited by putting normal food or treats around the room/playpen that they can search for and collect. If you really don't have the time or you don't have a safe room/play pen then even the bathtub will be a nice space which you don't have to watch them in so closeley.
making normal everday food, fresh food and treats will more difficult to get to, like inside a cardboard box and giving things more interesting to chew then wooden chew toys or whatever you use. Like a piece of kitchen roll or a tasty honey nut knaw
Hope at least something from this can help!