After the decades and billions of dollars spent trying to find anything – ANYTHING – on the Clintons, I think we can safely know the "rumors [that] apparently grew into something more" were just that: rumors. It all comes down to the ignorance and desperation of conspiracy theorists. They are desperate to believe only the worst. And, that desperation escalated and continues to escalate in the alternative reality they've crafted for the rightwing, directly leading to the assault on the capitol as part of the right's ongoing assault on democracy itself.
They've prove what Voltaire said so long ago (and, what witchhunters, facists, Nazis, Isis, etc demonstrate): “Those who can make you believe absurdities can make you commit atrocities.”