I’m a landlord....

You’re correct - the landlord CAN be sued for up to 3x the deposit amount. You’re within your rights to bring a case against him.

However in your situation, the fact you’re openly admitting the place was “trashed” (your words)..... the Judge wouldn’t be happy with you and would take the damages into account.

If I was you, I’d approach the landlord and come to some sort of agreement by suggesting you will take him to court for the lack of deposit protection.

The landlord should have protected the deposit, no excuses. But you also have no excuse for being disrespectful and trashing someone else’s house.

My advice is to come a deal, otherwise he’ll sue you as well.