In the video, I did see the foam separate, but not hit the wing. Boundary layer of air around the tank would have caused a vacuum (low-pressure) and "pull" the chunk back towards the tank, which I do see...
Yes, I considered a tank strike as well, and it is very likely.
Also, the after shot with the low res cam did not show any damage at all. If it were major damage the white exposed tiles would have shown on the image.