Fixed:
Turn 1:
P1 (4c1e) - buy Envoy
P2 (4c1e) - buy Throne Room
Turn 2:
P1 (3c2e) - buy Ambassador (reshuffle)
P2 (3c2w) - buy Smugglers (reshuffle)
Turn 3:
P1 (4c, Envoy) - Envoy (3c1e, discard 1e), buy Duchy
P2 (2c1e, Throne Room, Smugglers) - Throne Room > Smugglers > 2xDuchy, buy Estate
Turn 4:
P1 (1e, Ambassador (reshuffle), Duchy, 1e) - Ambassador > Duchy
P2 (5c) - buy Duchy
Player 2 ends with 4x Duchy, 4x Estate, for +13 VP. 'Course, now it's a little more obvious that the players are in cahoots...
*edit*
More fixed:
Turn 1:
P1 (4c1e) - buy Mining Village
P2 (4c1e) - buy Envoy
Turn 2:
P1 (3c2e) - buy Masquerade (reshuffle)
P2 (3c2w) - buy Silver (reshuffle)
Turn 3:
P1 (2c1e, Masquerade, Mining Village) - Mining Village (trash, draw 1c), Masquerade (draw 2c, pass 1e, receive 1c), buy Province
P2 (2c1e, Envoy, Silver) - Envoy (draw 4c, discard 1e), buy Province
Turn 4:
P1 (1c3e, (reshuffle), Masquerade) - Masquerade (draw 1c, Province, pass Province, receive 1e), buy Estate
P2 (1e, Province, (reshuffle), Envoy, Silver) - Envoy (4c, discard 1e), buy Duchy
Player 2 ends 2x Province, 1x Duchy, 3x Estate for +15 VP.