Firstly, nobody has the right to be on licensed premises if the licensee says that they cannot be there. So going to look at a CCTV to consider a matter to be right or wrong would have no value. It would only confirm (or not) mistaken identity and would not serve any ueful purpose. As far as the door person was concerned, they would be classed as a Front Line Operative under the Security Industry Authority cirteria and, as such be properly licensed. The requirements on wearing badges would be:-
"SIA licences are issued subject to certain conditions. Your licence can be withdrawn or suspended if the conditions are not met.
Front-line staff must:
Wear the licence where it can be seen at all times when working (unless you have reported it lost or stolen, or it is in the possession of the SIA)
.
Tell the SIA and the police immediately if your licence is lost or stolen
Tell the SIA immediately of any convictions, cautions or warnings, or charges for relevant offences whether committed in the UK or abroad
Tell the SIA of any changes to your name or address
Not deface or change the licence in any way. Should your licence become damaged, you should advise the SIA and request a replacement
Not wear a licence that has been defaced or altered in any way
Produce the licence for inspection by authorised personnel when asked to do so
Return the licence to the SIA immediately if you are asked to do so"
Suggest you have a look at www.the-sia.org.uk and, if you are suggesting an offence has been committed, report it to them and/or the Police.