Per Article 1 of the Constitution:
1. The House has the Sole authority to impeach.
2.The Senate has the Sole authority to try all Impeachments.
So either:
A. Trump hasn't been impeached yet
or
B. McTurtle can dismiss, or try Trump with any rules he chooses anytime he gets a hair up his ass.
There are no other options.
McConnell cannot dismiss without a vote.
70% of all Americans, including 60% of Trump's base, want a trial with witnesses and evidence. If McConnell successfully dismisses without a trial, the Republican Party will have signed its own death certificate.
Republicans promised the American voter that if they elected Donald Trump, Republicans would save the nation from Trump's worst impulses, and keep him in check, if they voted for a Republican House and Senate. Republicans renigged utterly on that promise and did NOTHING to stop Trump from separating children from their families, or locking up 40,000 illegals in internment camps without trial or due process.
All of these arrests and holding of illegals has benefitted the biggest donors to Trump's "Inauguration Fund" - the for profit prisons which are getting $700 per day, per prisoner to hold them in filthy, unsafe conditions, that violate the Constitution, the UN Refugee provisions which the USA has codified into law, and just basic human decency.
Real Americans want a President who isn't a national embarassment, and that means anyone other than Trump.