COLUMBIA, S.C. — Defense attorneys for accused double murderer Alex Murdaugh say in a new court filing that Curtis “Eddie” Smith, not their client, likely killed Murdaugh’s wife and son in June 2021. The 11-page motion, filed Friday in Colleton County, says that Smith flunked a lie detector test when asked about the June 2021 killings of Maggie, 52, and Paul, 22. “Smith decidedly failed a polygraph when questioned if he murdered Maggie and Paul,” says the motion, filed by Murdaugh’s attorneys Dick Harpootlian and Jim Griffin. “The reason Smith failed the polygraph when asked if he murdered Mag…