The Magpies went into the game at Loftus Road still in the relegation battle - a situation which took a turn for the worse when they went behind to an early Loic Remy penalty.
But Alan Pardew's side fought back to win the game 2-1 and confirm their Barclays Premier League status for another year.
There have been reports that the sizeable French contingent in the dressing room are at odds with the non-French players but Williamson feels that performance shows such talk is wide of the mark.
"There has been a lot said about it, a lot of speculation but you could see the commitment and the euphoria after the game between the players," he said.
"There is a lot of passion now and we are a very tight bunch.
"Maybe a lot is said about it in the media but it is all rubbish because the lads are tight, everyone doing it for themselves as much as each other.
"There is a lot of relief in the changing room and with the fans. It was a tough, tough game. We had to show resilience and character and I felt that is what was needed."