I think you are missunderstanding the purpose of 'facet.query', it doesn't change the base query used when faceting, it gives you a count of documents that match an arbitrary query.
what you are looking for is a way to "exclude" the fq used to drill down on the facet when computing facet results... https://wiki.apache.org/solr/SimpleFacetParameters#Tagging_and_excluding_Filters -Hoss
