I have not seen "America, Let it Shine" in person but I have viewed some exceptional close up pictures of it. Looks to me like she used gold metallic for parts of it and and a shiny finish thread in other portions. Three threads I know have a finish like that are Filtec Glide from
http://www.bobbincentral.com/ Superior Highlights thread and Isacord embroidery thread. All are tirlobal polyester threads which reflect light and they all have a beautiful silk look finish. In my Innova LA, my favorite thread to work with is Glide, followed by Isacord. Highlights is a bit fussy when it comes to tension when compared to the other two (it breaks quite easily if you have the tension too high, this thread likes very light tension) but once you have the tension set it is also a wonderful thread to work with.