Simply put your payback period to get to $0 would be likely 20 years it really makes no sense a company making $100 M a year growing at 6% at best is being valued at $2 billion when it has $-1.2 billion of equity.
Besides the fact you have to get positive equity before you can be paid leverage creates risk meaning I would use a discount rate of 10%. Assuming now it can grow at 10% thats $1 billion add then to the redundant debt and you have a $0 company.
But you guys say its $2 billion. I have no idea how people are so dumb.