I found a site that had two versions of the codes, US and EU maybe the sites you tried had only the US version. Here are both sets possible one of them will work:
Found at:
http://www.actiontrip...olidportableops.phtml
Special Character Passwords
Enter at the password menu:
JUNKER: Cunningham
THE-L: Elisa
E.APPLE: Eva
!TRAUMER: Ga Ko
ERBE: Gene
Hunter-n: Null
R.R.R.: Ocelot
PM-EMS: Paramedic
LQ.N2: Python
IVN =RV: Raikov
DARPA-1: Sigint
SATURNV: Sokolov
T.F-ACID: Teliko
PK +ESP: Ursula
MGA2VE: Venus
1+2-3: Zero
For the EU version use:
CUN=BOA: Cunningham
E.WASP: Elisa
016K/HYH: Eva
GAK.O: Gako Soldier
9-VIPER: Gene
ALL=0: Null
THE-SON: Ocelot
E.M.S.: Paramedic
GUFO: Python
SKAZKA: Raikov
D+ARPA: Sigint
Vostok: Sokolov
SHINE!: Teliko
ESP:ASP: Ursula
@VESPER: Venus
GALAXY-0: Zero