Sharp MX 5001 "Other User" account / job control

A Sharp MX 5001 is setup to prompt users to enter a pass code before they can print or copy.  The last audit of printing shows that "Other User" has been printing many documents.  
The manual states that "Other user" is a machine account, and that when a user enters an invalid code, it prints under this account.

If the printer prints anonymously when a user enters an invalid code, this would not only defeat the purpose of having user codes, but it would make accounting for who made the prints more difficult.

Questions:
When a user enters an invalid code, does it print an actual document under Other user, or does it just record the transaction under Other user and not print (so 4000 pages per quarter were not actually printed)..
Is this cause for concern, and need to be resolved, or are the number of pages printed under "Other user" just record of jobs from user codes that were not entered correctly?
If it is printing document under the other user, do you know how to limit this?