Good question, but lets state from the outset that Pinotage is not a hybrid. Neither is Ruby Cabernet mentioned further down.
Maybe we need to step back and define what a hybrid is. The Oxford Companion to Wine and The New Sotheby's Wine Encyclopedia both define Pinotage as a hybrid. Ditto Ruby Cabernet.
I have both the first edition and the latest, third, edition of the Oxford Companion to Wine and it cleary defines what a hybrid is and it
clearly does not define either Pinotage or Ruby Cabernet as hybrids.
Perhaps you can check again?