Author permission is not required to make a combo sticky. The forum policy is that all combo stickies are automatically stickied, provided they are written at least as well as the origionals, and contain links to the origional threads for historical purposes and credit.
Going to an existing sticky, hitting reply with quote and grabbign their formatting and incorporating it into your own expanded sticky is not only allowed, it is encouraged.
I would encourage you to make a general "Garuda forum Sticky, threads of interest and FAQ with videos of doom" sticky or something along those lines and combine one or more of the existing ones with your video information into it.