Partner X claims he didn't receive a lead I sent, is there a way I can tell when and where the lead was sent? Yes. You can check actions taken upon a lead via the lead history log on the detail screen. To access this screen, you would click on the lead ID on the lead list. The history is shown on the right of the detail screen.

Potentially there is a Customer Feedback email that gets sent out. Where do I find the customer's response? This data would be found on the Lead Detail screen.