Quick points here and there.
Breach of Privacy laws is not - that I know of - a criminal offence. Not every time you don't comply with the law, it's a criminal offence you commited.
Defamation is not a criminal offence, although it could give rise to civil liability.
Attempted theft is an offence. There could be enough to charge the guy with that. But could he be found guilty?
That he intended to steal the bike, on the basis of the footage, is probable. But in our Courts, thankfully, to convict someone you need to be certain beyond reasonable doubt. A awful lot more difficult to prove than under the "on the balance of probabilities" standard.
So it would all come down to what the extend of the conversation with the shop owner was, and to what the dude could say in the record of interview if police were to get their hands on him.
This is because theft, and attempted theft, can be proven only if the (alleged) thief had the intention to permanently deprive the lawful owner of the item taken (unless the item is a MOTORvehicle - which the bike isn't. The element was removed for the theft of motorvehicles to cater for the "I've taken it for a joyride, I was gonna give it back!").