They'll be joining long-standing coach Will.i.am
The couple were married for 59 years after meeting in school
Singer claims his race has always been questioned due to his skin tone and curly hair
Singer recently said that he was 'paranoid' about homosexuals during early career
Veteran singer faces backlash from LGBT groups over remarks
Veteran crooner says he "feels sorry" for Jones
Pair are said to have not spoken for two decades following rivalry