I think 24- 105 is better, for one thing, the focal length is long, and for another, the price is cheap. It doesn't matter which aperture is smaller. It is also possible to blur the telephoto end of 24- 105. Besides, shooting video does not need such a high resolution as 24-70.
If you want to blur, you still need to use fixed focus. However, during the wedding and filming, there is no time to change the avatar. When making a microfilm, the promo is easy to change.