Islamic Coins Identification And Authenticity

You are correct in the link
https://en.numista.com/catalogue/pieces75413.html

Personally I am suspicious of the authenticity. The calligraphy is crude compared to the piece cited, some appear to maybe have been made with the same dies, the patinas look a bit odd, and of course Pakistan is a hotbed of coin forgers. Having said that, none of that makes it definite that they aren't authentic. Maybe some more silver tests and better weighing (though there could be some variability in authentic specimens) might help. Kitchen scales aren't adequate for weighing coins; much more accurate digital scales are available for under $20. A density or XRF test might help determine if silver. The rough surfaces and flat, not-sharp writing make me think of casting. Do the edges show casting lines, sprue marks, or file marks?