Hi Kevin,
Do you know the BI_COMMAND?
http://help.sap.com/saphelp_nw70/helpdata/en/43/ef05462480025ae10000000a1553f7/content.htm
This I think can help you achieve your business requirements.
You should build this URL in the Excel of your dashboards dynamically to retrieve the LOV you want to pass and then link your URL button to this dynamic cell.
Alex