No. You most definitely do not want to do this. Remember Pacman frogs will try to eat anything it can fit into it's mouth and if the Chubby frog is small then you know what it'll try to do. If I'm not mistaken that Chubby frogs secretes a toxcin that maybe fatal to your pacman. Pacmans are meant to be housed separately. If you don't have the space to provide for separate arrangements then perhaps you may want to consider giving up one of them.