The statute, 2C:58-4, makes the local polilce chief or superintendent NJSP responsible to "determine and record a complete description of each handgun the applicant intends to carry". Now that seems to place the obligation solely on that officer, and afaik (IANAL) there is no penalty or violation defined anywhere for a permit holder carrying a different handgun, but it would be a very small surprise to see a prosecutor or judge stretch that requirement into such a violation. The memo that you refer to has been pretty thoroughly debunked as bogus on this forum.
99% agree. Personally, I want to be very careful about who gets to define "anyone who illegally uses firearms" for the purpose of administering severe penalties for that use. There are far too many people holding elective or other government office who hate anyone who exercises his or her constitutional liberties, and would welcome the opportunity to punish (or eliminate) all who seek to do so.