So. . . Just imagining that President Obama releases a smoking gun with clear fingerprints-- [View all]

i.e. documented collusion between the Donald and Russians. . . Evidence showing the tRump campaign was in on the whole thing, etc. . . .

WTF happens next? Is it the same scenario as an impeachment? I don't think he could ever take office, nor could his VP. . .

How the fuck would this be handled? His entire CAMPAIGN is suspect now, so I can't see how they could choose a successor under THESE circumstances? ("these" meaning IF President Obama, etc released a smoking gun.. . .)
On edit-- I am 110% certain that Obama would be delighted to release this information, as he would be protecting the country.