The longer clip posted from ITV in the twitter feed above is more useful.
I cannot see how he felt personally threatened by her.
He pushed her up against a pillar before turning her around and frogmarched her out of the room.
He is not a security guard.
At no time she seemed able to harm him or he seemed worried that she would.
The poster above who seems adamant she posed a threat to him could explain herself better in the context of the longer video.
I hope she seeks legal advice.