Champ,
I don't think Quasar will stop mine development on AGS's request. AGS will keep on paying when handed the bill.
If they did stop payment then this would create other legal headaches for themselves.
The concern to AGS (if I'm correct) is not about the development costs but the total operating costs (US$25/lb). If this is the case then AGS will go ahead with obtaining development funding but keep on disputing the operation costs.