An alternative to solve the duplicated transactions :
NEM group handles one case ('stake reserved _money_ account') at a time as follows.
1. NEM group sends PM's to suspected names (possibly only 2), who claim that
they own the account. NEM group asks them to send 1, 2, ... or 10 NXTs.
* Extra check, if there is a very active and anxious fraudster: Each candidate is asked to
send a different amount of money. So that fraudsters can't explain
that they just sent the 2 NXts from THE account, when they saw that kind of transaction
from THE account to NEM account. Explanations are not enough, coz they were asked to send 4 NXT
2. All the receivers send the requsted money from their accounts.
3. NEM group compares the sending accounts to the original 'stake reserved account'.
4. NEM group returns the NXTs, which were sent in this extra check.
If the anxious fraudster sends some NXTs, they are kept for the NEM group
This IPO has good features by being so public, but some of the process must not be public.
Maybe at this time, the not public part is the last verification.