The real story here was that they had engaged in illicit surveillance of Trump campaign officials for months leading up to the election. They thought they'd get away with it because they assumed Hillary Clinton would win the election, and nobody would ever learn about what James Comey and mutants like this Stroker dude were up to.
When Trump won the election they knew their malfeasance was going to be uncovered by the incoming administration, so they concocted the "Russian collusion" story to retroactively justify the surveillance.
It's really as simple as that. And it's the illicit surveillance and the shady circumstances surrounding the FISA warrant that was used to give the whole operation legal cover that's going to cause the whole thing to unravel.
Exactly. If they don't indict someone for something they are themselves in legal jeopardy.