A more plausible explanation is that the Clintons threatened to use their own M.A.D. "nuclear option" - the 2000 plus (not the 800-900 figure commonly cited) missing FBI raw confidential files containing enough dirt to destroy most of the members of the Senate - if the Senate leadership didn't back off and rig the game so that the problem would just fizzle-out and fade-away.
This accounts for the unprecedented closed-door session where the Senate voted 99-0 in a secret vote to change the long-established rules for the presentation of evidence and conduct of the trial. These changes made it impossible for Henry Hyde and the House impeachment managers to present a real case and get a fair hearing, and guaranteed that the American people would never see the bulk of the evidence. From the moment of that 99-0 secret vote to change the rules and rig the game, the rest of the Clinton impeachment process was mere political theater.
I would truly love to know what actually went on in that closed-door Senate session, but I doubt we ever will - the political code of omerta will probably hold. I suspect it was simply a case of the Clintons letting it be known that if he was going down, they'd take the rest of them with them. Presented with that threat, even Senators who were not personally vulnerable to the threat probably concluded that this would effectively bring down the American government, so they went along "for the good of the country".
If that was indeed their rationale, however, I personally believe that in the long run it will prove to have been misguided.
More plausible?
That is tinfoil hat stuff.
The fact of the matter is that given the choice between Bill Clinton and Al Gore, I would gladly pick Bill Clinton. Al Gore is certifiably insane. Bill is just a self centered egotistical womanizer. Clinton did nothing and let the country go into the toilet. Gore would have flushed it.