I've been wheeling out there for many years and never got stuck once. Yes you can drive around the "puddles" but where's the fun in that? I have not encountered a puddle yet that could stop my Libby. Virtually all of it is packed sand with some loose sand here and there but if you drive through that wisely it won't stop you.
As far as trail maps, go to the ranger station at Four mile Circle in Southampton, Burlington County. They should have them. I've never needed them myself, i used USGS Maps that i got at a local map store. Also use google Maps in Satellite view.
One stop i recommend is Apple Pie Hill, near Chatsworth in Woodland TWP. There is a fire tower on the hill that provides a great view of South Jersey. You are allowed to climb the tower so long as you don't try to burn it down. You can see Atlantic City and Philly from there on a clear day.
oh BTW, tell you buddy with the VW to keep the local tow truck drivers number on speed dial, he's gonna need it.
2. No Alcohol.