He can be inaugurated for his second term at 12:01 AM on Jan 20, 2021 with just one SCOTUS. No need for a big outdoor celebration. POTUS does not need be an outdoor target.
VP Pence should just reject the fraudulent electors and let the state legislatures decide. If they cannot decide, then let the House/Senate decide. It follows the constitution.
Trump WON 49 states.