This is simply not true.
Oliver had 3 tackles, led the team in QB hits and could be seen several times successfully anchoring against doubles and hustling downfield to run down ballcarriers.
Rousseau's only "play" was a single assisted tackle in the 4th qrtr (it was not a tfl) and he could be seen multiple times standing around unengaged, waiting for his teammates to finish plays.
Oliver has not been good this year, but he was not the problem yesterday.