Yeah. If you really want to. Presuming 112233 has their own mailbox and you still need them to access that, but you want the envelope key to prompt for pw 114433 first and they can press * to go back a level and 'please enter extension and # sign' for 112233 again to get their own voicemail, sure.
Presuming AAM on CM/SM, let's say the voicemail number is 110000 and that, in AAR, hits route 11 for trunk 11 for sig 11 to SM with the digits going in SM to AAM, then...
Make the phone's envelope key dial 120000, which in AAR goes to route 12 to a new sig/trunk 12 you make (that looks just like 11) but in the private unknown numbering table, you'd have an entry that says "112233" length 6, delete 6, insert 114433, for trunk group 12, with total CPN 6 digit.
That would make the envelope key for 112233 pick a different trunk where the CPN can be manipulated to get what you want.
Just make sure to pick a sig/trk # higher than the one you use for voicemail.