The police are required by the rules of criminal procedure to provide you or your attorney, if any, with all evidence related to the case.
However, based upon your assertions, it appears the police may have destroyed exculpatory evidence. This is called spoliation.
I strongly suggest you retain counsel experienced in dealing with the police department particularly and OUI cases generally. Your state and local bar associations can assist you with referrals.
If you can get the video you can use it. If you can't get it from that next person's attorney, then you/your attorney can subpoena the booking room video by expanding the time frame you want the video to cover to the time after yours ends.
Your attorney should be able to acquire the video referred to. The issue is not one of who's video is involved rather whether the video contains info RELEVANT to your case or containing exculpatory evidence.