I hope this message finds you well, present circumstances excluded. I am a licensed attorney with over a dozen years of litigation experience. It is a pleasure to assist you today.
Based on what you have shared with me, you have a cause of action for breach of contract as well as for vicarious liability of the owner relative to his security personnel. You can sue the personnel individually as well. The vicarious liability issued would loop the owner in if they cannot or will not pay on the judgment your receive. You also have causes of action of fraud and arguably gross negligence as well. Since this harmed your business and personal reputation (which is tied to your business) you have a cause of action for tortuous interference with business practices as well.
In short, you have a number of different avenues under which you can sue this person and the security team - all of which can be filed under the same law suit.
I would put him on legal notice of your intent to sue via certified letter with a return receipt. Tell him you are open to discussion as to how to avoid this suit by his attempts to make you whole. Tell him he has 5 business days from the post mark to respond. If he does not, you are going to sue.
He likely will not respond and you can then file suit. I wish there were an easier way, but you will win once you get into the court system.
Let me know if you have any other questions or comments. Please also rate my answer positively (THREE OR MORE STARS) on the ratings bar on your end so I can receive credit for my response.
Thank you and best wishes!