There's not any output for most of the BFBC2 servers, out of there for example: http://www.gametracker.com/search/bc2/
It just prints:
ADDRESS PLAYERS MAP RESPONSE TIME NAME
And nothing else. Also specifying -xml flag gives empty XML.
I don't really know if it might be an QStat bug or some gameserver issue that prevents QStat from getting stats.
If this is still an issue please open a issue / pull request @ https://github.com/multiplay/qstat