You want the circular fan to create a gentle breeze on the plants, and typically want it pointing at the top of your plants. I keep one below my plants, pointing at my containers, and one above. I didn’t see that gentle breeze in the video.
As far as topping, I would wait, the bigger girl seems she wants to grow roots (Fresh transplant?)
Here is my mentors grow guide, this is where he covers topping. Hellraiser is God when it comes to growing. I follow his methods step by step. I couldn’t be more happy with my grow.
Yes, prune off those dead leaves, not doing you any good!