How did your friend got the idea that doing a rotation at a hospital that has AOA approved programs would make you ineligible for residency positions in other states? Maybe I just don't understand your question, but it seems that your fellow classmate doesn't know what he/she is talking about. Completing a rotation at a hospital has no bearing on where you will do your residency (unless you are showcasing yourself at that hospital). Wyckoff has both AOA and ACGME approved programs:
http://www.wyckoffhospital.org/gradmed_resprogram.htm. It doesn't matter whether you are graduating as an MD or DO: if your planning to do your residency there, then it would be in your best interest to rotate there.
Or maybe your friend was onto something. This was taken from a post (courtesy of realruby2000 and Apollyon) in the Emergency Medicine forum:
http://forums.studentdoctor.net/showthread.php?t=169091
"is there any true disadvantage to doing 4 or 5 away rotations? I know I probably won't be able to take as many "fun" electives but other than that what other ways can it hurt me?"
"State licensure - some states won't accept training outside your home institution (regardless of the rotation being at an ACGME-program place), and states that dictate # of weeks are in the area of 68-72 weeks of clinical. I did one away, but had 80 weeks of clinical. If you do 20 weeks elsewhere, you might not have any wiggle room to be qualified in some states. Unfortunately, you have to look at the laws of each state individually. The Green Book has good summaries of what is needed for licensure in each."