The easiest way to see which reports have been shared and/or downloaded is to:
Open your project
Open the Feedback area
Click Actions > Export to Excel
Open the Excel spreadsheet and look at columns S and T to see if the person being assessed and report reviewer have received the report.
The values in columns S and T will be one of:
"Not yet shared" if the report hasn't yet been shared
"No" if it has been shared but not downloaded
"Yes" if it's been shared and downloaded.