If they are going to wind the company down and pay a one-time 2%...

If they are going to wind the company down and pay a one-time 2% royalty on the lifetime reserves number, that's money to the shareholders and might be taken as a buyout price.

But if they are paying a 2% per annum royalty on actual sales, then you have to deduct GWR's ongoing expenses and other development costs, factor in any existing debt, etc. That gets dicier to project a market cap based on that alone.

It's very misleading to project the sales royalty per share against the current share price and imply that the sales royalty per share is what the shares should trade for. Maybe yes and maybe no, but you didn't complete the analysis.