They can serve your video ad with control groups and test groups. One group sees your ad, another doesn’t. Then they answer questions about your brand.
Since the only difference is the video ad you’ll have a great response to it. Google Consumer Surveys will either show your ad made an impression on your brand or not.
Easy answers for you. Much better barometers than just views.
Here’s a YouTube link with more info: https://www.youtube.com/watch?v=ZnXtoSF-kwU