As mentioned already, no showers at the Devil's Tombstome but the DEC will honor your camping permit at North South lake so you could take a shower there for free. It's about 9 miles away north on Rt 214 to Rt 23A east to Haines Falls.
I would not camp at the Devil's Tombstone unless one could guarantee WR1 and WR2 for my week's worth of entertainment.
Unless you are female, but I don't feel as threatened by them being male, although maybe I should??? Who knows, thats where the entertainment lies.
The bicycle spot is a good idea, I first did the DP thing as three separate hikes using bike spots at Roaring Brook road in Elka Part, to do the Indian Head, Twin thing and also at Diamond Notch to do west kill from Notch Lake and I think I did a spot from Notch lake to Roaring brook to do Sugarloaf and PLateau once too.
But if you're interesting in doing hunter, take a look at Diamond Notch Leanto. It is easier to get to on a late friday night than Devil's Acre (less elevation gain). It is about 2 miles from the end of DN road (unless you are brave and have an SUV to drive to the actual trailhead). or it's a closer and easier hike from Spruceton Road. Then you can do Hunter in a loop and SW hunter or Rusk if you want too, you should have enough time with an early enough start and a average pace and then return to DN. Or you might just do Hunter and perhaps West Kill and then back to DN.
Day two, you could hike out with a real early start and go do the eastern part of the DP after a bike spot or so. Really ambitious would be to spot a bike first at Prediger (hide it well into the woods as not to piss off the person living there and his/her thousand of "no parking" signs
). Then on Day two, you can hike all the way to Prediger and bike back to Notch lake.
Jay
P.S. If your dog can handle the length, elevation gain, it is probably EASIER for the dog.. 4 paw drive, ya know...