You are correct, and I've never seen nor heard anything after 2019 indicating that her grave had been found.
Posted earlier in this thread:
Officials had hoped a Sept. 5, 2018, excavation at Citizens Cemetery in Flagstaff, Ariz., would unearth the lost remains of a girl dubbed Little Miss X. The teenage girl’s body was found in the Grand Canyon in 1958, but, after an initial investigation turned out to be inconclusive, the remains were reburied and lost in the 1960s, officials have said.
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However, tests on the recently recovered remains show it was not the body of Little Miss X, said Lt. Gerrit Boeck of the Criminal Investigation Division of Arizona’s Coconino County Sheriff’s Office.
Connie Smith mystery remains unsolved