The following is a detailed t'shuvoh (responsa) authored by Harav Eliezer Hool Shlita, explaining the differences between witchcraft, divination and Darkey Ho'emori etc. according to rishonim and achronim. It proves emphatically that lead pouring is in no way a violation- chas vesholom- of 'Tomim Tiheyeh Im Hashem Elokechoh" or any other issurim.
Although the discussion is specifically about the pendulum, 'lead pouring' can be classified as 'Darkey Ha'Emori' which is clearly permissible for a refuoh.
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