I can't, never had one
The connection to the rear wheels via the AWD transfer case is direct, so Park Pawl should hold regardless of front drive line being connected or not
Front drive shaft is chain drive but via a viscous coupling, so I could see rear drive shaft removal causing slipping in Park
But people have reported "creeping" with front drive line disconnected, not a full disconnect, just a movement over distance depending on slope.
Some could be discounted on Ford shifter issues, common problem, not fully in Park, but all reports.........??
Disassembled view of BW4404 AWD transfer case seen here:
http://www.explorerforum.com/forums/index.php?threads/school-me-and-you-on-viscous-couplings-bw4404.225515/
I don't see a way it could slip the Park pawl, but hard to discount all the stories
And certainly worth a "heads up" to someone considering not having front drive shaft installed