Board Thread:General Discussion/@comment-26835334-20160915033351/@comment-5126335-20170524132205

While it's not quite 100%, I think it's safe to say that I've identified the light-up dance crew at the beginning of the video as Light Balance from Russia. They were on BGT a few years ago.

The group in the video and Light Balance have some very similar looking outfits and Light Balance posted on their Facebook page that they auditioned for AGT, so it's most likely them.