Are you an investigative reporter with evidence or just making that up? What you're saying makes no sense. If they knew about his affair do you seriously think they wouldn't have exposed it at the same time they made up 84 false ethics charges and were trying to defend Clinton from Monica-gate?
It was clear at the time that the charges regarding his college classes were bogus and easily fought.
I said at the time, “somebody has pictures”, because his unwillingness to fight against false charges was so out of character.
Clearly is was a Republican that blackmailed him, as there was no upside for going public against “our team”.
So, it was a different “they” than you suggest.
It is also clear now, that the affair was ongoing at that time.