I didn't see a "punisher" refered to in Dodge body builder specs but did see a 1500 R/T with the hemi/20" P tires and a 5025 lb tow ratings. HP doesn't equate to big tow numbers as the Dodge SRT10 1/2 ton truck with the 8.3 V10 at 510 hp/525 ft lbs engine shows. These trucks are for lots of go and very little tow/haul.
Other Dodge "sport trucks" with the 3.55 axle shows a 8200-8500 lb tow ratings. He will have to find his trucks particular tow rating from his Dodge dealer.
As all 1500 Dodge trucks with that small GVWR and wimpy 3900 lb RAWR numbers the 5th wheel will have to be a small unit with 800-900 lb dry pin weights.