Don't know if this will work for you... We have multiple tape libraries at different sites. We also use a different location for each sites "offsite storage". Normally we use vault tracking to keep track of the tapes for us. It can give us a list of tapes to come out, and tapes to go in.
I was able to duplicate our "tapes due back" list by using the Media Information Report.
On the General Tab, I chose "Spare" tapes only.
For Libraries, chose only the library in question, and only selected the Media Location of "out".
we don't really have a media repository, left this tab alone.
For location, I chose our offsite location associated w/ that tape robot.
Storage Policies, I chose those associated w/ the tape robot.
I chose a time range of "No".
Maybe you can play with this?