I asked a person to make me a YouTube video and I need the video to be original. How can I check if it has already been posted on YouTube?
Do you know the title which you asked this person to post on your behalf? What account did you ask them to post it to? Did this person let you know when the video will be posted? I'd start there first, but also search for the name you provided.
There are many copies of 'original' videos on YouTube so if it's a popular video, it will likely be copied to multiple accounts.