Richard Smallwood scored the winning penalty as fourth-placed Rotherham came from two goals down to register their second successive promotion. Having trailed 2-0 at halftime, Alex Revell scored twice against his former club. Moses Odubajo and Dean Cox had opened for Orient.
The 51-year-old Evans is rebuilding a reputation after a "contract irregularity" scandal at Boston followed by a suspended prison sentence for tax avoidance. He then took Crawley into the Football League for the first time but suffered a stadium ban after an incident in the tunnel following a game at Bradford.