I think that you would have a much stronger legal case if you have different recordings on multiple days, showing a habitual pattern of disregard for laws.
A single recording is always written off as a blip and "accidental oversight", and owners usually get off, and courts give benefit of doubt.
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I looked into it further and " -timestamp" is not the mechanism for obtaining a proper timestamp in the file's metadata. There is a different approach required, using the "-metadata" options.
You can download the updated script that does that correctly from my GitHub account. The link for the updated file is this.
These are the changes:
Added logic for --storage option, to specify full path to video output repository.
Added logic for --test option, to generate test-pattern video showing timestamp as specified.
Added logic for --purge option, to safely purge all videos older than a specified age in days.
Added logic for FFMPEG -metadata options, to correctly embed creation_date value in the video file's metadata.
Changed default setting to provide uniformly light-coloured background for the in-stream live timestamp.
That is my baseline version of the script, which I don't plan on modifying any further, since it accomplishes everything that I see as necessary.