London Silver Fix Will Be Scrap After August 14th

I think you have the wrong idea what the London Fix is. Basically it is just two banks discussing what their customers are willing to buy and sell silver for and settles on a price to publish. They don't regulate anything, they don't fix any prices.
The U.S COMEX determines the " next day"s " price at the closing bell. This is what traders and most dealers/resellers use and will continue to use after the London fix is gone.

https://goccf.com/t/177657