Bluebirds defender Bielik was involved in a physical altercation with a fan as he went to retrieve a ball from the crowd late in the second half.
After the fixture, Hampshire Police said it had into an incident "in which a teenage boy was reportedly the victim of a common assault".
Mousinho to Cardiff City players following the incident and condemned the behaviour of the supporters involved but on Wednesday, during his pre-match media commitments before Saturday's fixture against Charlton, he said the comments were based only on the account he had been given of the incident.
"I've now seen the footage and my comments post-match were entirely based off what I was told," Mousinho
"When the altercation kicked off I couldn't see it from where I was myself, the referee then spoke to us and his words at the time were very clear that he had seen the incident in its entirety.
"He said that as Krystian went over to get the ball, the fan slapped him, and a second fan threw a ball at Perry Ng's head. "
