I wonder if by banned substance they could mean recreational drugs. I can't see how UKAD, VADA and the BBBofC could all let the fight go ahead if it was PEDs, reeks of corruption if it was.
Still, very bad for Whyte, his reputation will be gone and this could take years to resolve. If he did take PEDs then that's probably it for him. Interesting looking back now as he was saying after the fight that camp had been full of issues.
As for the Ruiz Joshua rematch, I honestly wouldnt be surprised if it didn't happen.