Recovering lost MP4 files after iCloud migration on Macbook

I had avoided using iCloud since I got a new macbook (about 3 years). A few months ago I recieved an email that I needed to have more available space for the next system update. My decision to go to iCloud was made with apprehension but, it was my decision. It all seemed to go ok. There were about 100 or so MP4 files on my laptop that seemed to have disappeared. They weren't in icloud and also gone from my macbook. I contacted Apple support and all they could tell me was that I should have had them backed up. So, I tried everything I could come up with. I used Disk Drill without any luck. So, I have 2 questions:

1) Any ideas for me to get the files back from my drive on macbook?

2) I thought iCloud simply copied from my macbook but, this seems it took the stuff completely off?

I have started saving the stuff I really want to keep to my LOCAL drive since this happened.

Thanks

[Re-Titled by Moderator]

Original Title: Lost mp4 Files