I would be extremely hesitant to keep anything with Dwarf Puffers considering they can be rather nasty and territorial. I don't have any personal experience with them however, so maybe someone else can refute this.
i would say no. either the dwarf puffers would nip at the frogs or the frigs would try and eat the puffers = very stressfull. Are you planning on puffers for the 5G? that tank might be a bit small die to their territorial instincts.