@Alexander, you could try to talk airbnb into considering the cancellations as caused by the same event and error and that they should apply only one penalty to all of them, not one to every single one. You have understandable cause for your error and it would encourage you to continue hosting with the same account and on airbnb.
Call them and keep trying. Try to get a case manager or get higher up and plead your good will. That you tried to minimise damage to guests and airbnb image should help, insist on that.
When the airbnb founders started to lodge students on an airbed in their living room, they did not have permission to do that either. Their "illegal" idea is worth billions today.
Unfortunately, this forum is getting more hostile by the day. And I could not even say if the unsolicited attacks are worse or the unmotivated All-is-well-be-happy nonsense the same people post on other triggers. It's just pavlovian reflexes is action.
I'm very sorry that you got that straight off when asking for help.
Good luck for your negotiations!