We are always on the hunt to give you the most complete data set available from Amazon. We continuously update dash databases with the most recent API data availability, coinciding with Amazon's (mostly) monthly API releases. With that, data for the following ad units is not yet fully released from Amazon as of 2/25/20: Sponsored Brands Video, Product Display (as part of Sponsored Display)
If you are running either of these ad units, your dash data will not include the corresponding performance data and will therefore be understated to the Amazon interface by the ad metric amounts related to the campaigns in question.
Sponsored Brands video data is rumored to become available in April of 2020, while Product Display data will be available in the upcoming March 2020 dash database update release.