Warren Haynes, late of The Allman Brothers Band, and Govt. Mule.
Excellent guitarist, but hard to picture fitting in with the Dead, musical style wise.
I’ve seen Warren with the Dead before. They intentionally avoid getting someone Jerry-esque. I sort of wish they would get someone Jerryish—clean, sparkly tone, melodic, jazzy. But they don’t want to, so be it. Warren is very servicable. He can sing, he can play, he knows what he’s doing. I get very, very tired of the many Duane/Dickey clones out there—the Les Paul/saturated tone, the BB King licks through a Marshall, etc, but he’s got soul and he’s competent.