@Daniel Mendel, I think the problem is with the default separator used by ColdFusion. You have data that is having a ',' in it and the default separator in CF is ',' incidentally.
Change your query like this -
WHERE name NOT IN ( <cfqueryparam CFSQLType="CF_SQL_VARCHAR"
value="#ValueList(qTags.tag,';' )#"
list="Yes" separator=";" />
)
Just change the separator in valueList to ';' from default ',' and also set the QueryParam separator to ';'.