NotesACL.getEntry(String) can only find
direct entries; see usage notes in Designer Help:
"If a person is not listed explicitly in the ACL, but is a member
of a group listed in the ACL, getEntry does not find that person's name."
A possible workaround is to use NotesSession.evaluate(@UserNamesList),
which should return a complete list of the current user's names, roles
and groups the user is a member of.