How were Sartanism and Adgharism ever related? Sartanism is an offshoot of the Church of Ibladesh. Sartanism viewed Adgharinism as idol worship.
The Agharinists worshipped Sartan as one of their gods. They called him a different name, but they recognised him as the same god the Sartanians worshipped. I'm surprised you didn't know that.