I’ve never had the milkman show and what are the keys for when you finish a game?

1. If you started your game before Oct 2018, the milk truck arrived in Oct 2018, gave rewards for 30 days ending, and ended with the receipt of the Delightful Dairy decoration. If you began your game after that, you should have received the milk truck rewards for the first 30 days of your game and ended with the Delightful Dairy decoration. If you did not receive the Delightful Dairy, ask customer support through the "help" button in the game settings (green gear icon).

2. The gold keys are part of the Detective Needed Challenge. It is a time-limited event, where you collect keys to win rewards as shown when you tap on the stopwatch icon when the event is active. There you will see how many keys you need, how to earn them (from scenes or cases or both), what rewards you can achieve, what is your progress, and how much time remains before the event ends. Keys reset for each event and do not carryover.