I'm having issues with filtering not working in general - it's sporadic
and odd, and my usual workaround is to make a copy of the report and
voila! filtering works again. I realize my first instinct is to find a
workaround, and it should be to open a support ticket. So, I just tried
copying a filter to create a new one and the filtering does not work.
It's not the same criteria you're using, but similar. I think I'll go
ahead and open that support ticket now...