I simplify the problem as follows:
Given a Excel 2013 pivot table report with one dimension X linked to a slicer, sourced from SSAS 2012 tabular model (v11.0.3000.0), put on Sharepoint 2013, and viewed by Excel Service. If applying row filtering makes X become empty, the slicer will fail to refresh, halt the row filtering, and the report will display the cached information to the Sharepoint user.
My question is:
1) Why the slicer refresh fails if X becomes empty? Should it display "all values are filtered out"?
2) Is it possible to clear the pivot table caches and slicer caches before putting the report on Sharepoint 2013? That's may be my workaround if no solution can be found.