To move root to USB does not make a difference.
I’m referring to this post. No, I don’t think you read it …
SD and USB might have been bad right away, but that would have been a big coincidence.
Most likely your data was already corrupted when you moved it to USB.
Yes, start from scratch. And check the Pi HW before that.
To use different HW minimizes , but does not mitigate the risk the way a backup concept does.
No, I still don’t think you read it 
You could create a SD clone and instruct all of your family members how to install it in a Pi just in case.
That’s what I did …