The American A-lister, who was open about his alcohol and drug abuse during his career, committed suicide back in August at the age of 63 after battling depression.
Tyson revealed in an interview with Howard Stern that he met Williams at a meeting while they were both dealing with depression.
"This is very interesting," Tyson said on SiriusXM Radio. "When I met him, he said 'I was waiting for you'. He started telling me about somebody I was purchasing from.
"I said to myself, how does he know this lowlife dealer I know? They shouldn't even be in the same state as each other. You'll go to any measure to get high or to use when you're in that situation. So everyone knows everybody."
Tyson has dealt with substance abuse during his high-profile career.