Did some more digging today and you can now add the entire Bill Haley & His Comets to the great beyond... I totally missed the news this year, but the last surviving member, bassist Al Rex, died back in May (at the ripe old age of 91).
The Platters once Herb Reed died a few years back.
The members of the classic Platters line-up that appeared on their big 50s hits (Tony Williams, Herb Reed, Paul Robi, Zola Taylor, and David Lynch) are all deceased. But Sonny Turner (who replaced Tony Williams in 1960 and sang lead on their last few hits in 1966-67) is still alive.