Upon what basis did they qualify him? The term "no Person" from within the eligibility requirements from within the Constitution certainly trumps Congressional "discretion" in ignoring or following the Twentieth amendment, section three.
Obviously they pulled the qualification out of their butts. Unfortunately, it is done and over until some state passes a law requiring proof of being a Natural Born Citizen or until he is impeached and tried.
Congress has the only real say in this from what the constitution says. States can force proof for qualification to be on the ballots. But after they certify the vote totals and send the electors to vote in the Electoral College and that vote is sent to the Congress it is Congress’ call with no appeal.