Is this miswak (tooth stick) method from authentic sunnah?

I was watching this [clip](https://www.youtube.com/watch?v=ZD0_d5upgYM) from the founder of [Dawateislami](https://www.dawateislami.net/) . There are some things which are new to me about the use of miswak (tooth stick): 1. Miswak shouldn't be longer than a hand-span as it will cause Satan to sit on it [0:22] 2. One should not clinch with the fist as it will cause piles [0:37] 3. While washing miswak, recite salawat or better to include "Ya Qadir" [0:47] **Question:** Are these practices from the authentic sunnah?