try running an inventory on the library itself... if the tape(s) are
actually outside the atl, this will update the info you see with the "mtlib"
command.  ALSO you need to note the status with which the tapes show up in
the output of the "mtlib" command... if they show up with a FFFA that is a
manual eject which would say they really aren't in there :-/
To physically purge any library records you may use the
        mtlib -l/dev/lmcp# -C -VXXX### -sXXXX -tFFFB
where # is your library number, XXX### is your tape volser, and XXXX is the
current status of the tape shown in the mtlib query of the volume...
Yes, if the tape actually exists in the atl (say in FF00 insert mode) and
your tsm system thinks it is not in the library inventory (of tsm) but is
actually a private tape, an "audit libr blah" will NOT add the tape to your
tsm library inventory, you will have to do that yourself with a "checkin
libvol ..."

hope this helps...
later,
Dwight