You can make an argument that Trump, himself, didn't actively collude with Russia with regard to the election. He's probably not smart enough. It's less clear that underlings (Kushner?) didn't provide somebody with demographic/precinct analysis that assisted Russian disinformation targeting.
Trump's personal problem - and what probably drives his terror over the Mueller probe - is that he appears to have been involved with Russian criminals - not necessarily Putin/FSB, but still - over a longer period of time, using shady real estate practices to allow the Russians to launder stolen money...and of course, Trump would have profited handsomely from that. After the bankruptcies, no respectable bank would lend him money any more, so shady real estate deals were his only source of income. That's separate from election malfeasance, but it's a major felony, and not something that Trump could avoid prosecution/incarceration over.
I don't know whether Trump will allow the Mueller investigation to run its course or not. But NY AG Schneiderman, with help from former US Attorney Preet Bharara... Trump can do nothing (short of mob hits) to stop that investigation. Because NY will be bringing state charges, rather than federal ones, Trump has no power to pardon himself, or his family members, or his minions...and because that means he can't guarantee a Michael Cohen, or Jared Kushner or other underling won't actually go to prison, he can't protect them from deciding to turn state's evidence to save their own hides.
The rats should start jumping ship sometime in the next few months.