I understood: you store your backup and your CCTV files in one vault. If you want to restore from your backup, you do not want to download the complete vault.
I would recommend to separate your backup and your CCTV files into 2 vaults.
Why? Because if you have a look into your cloud space you’ll notice that you are not able identify wether an encrypted file/folder belongs to a CCTV or a backup file. You only can identify complete vaults.
But besides my recommendation: there is a solution.
You can access your vault only online and then download the backup files only without local sync.
This can be done with cyberduck. How do I use Cryptomator without local sync?