Have a look at the frame 0.12 seconds in. You will see an identical while light at the top about 1/6th the way in from the left had side as you look at the stage. You will also see two more similar lights as you glance right from the position of your left hand going up right at around 45 degree angle. You will also notice just above these lights there appears to be a lighting bar and you can make out the silhouettes of two stage lamps centre top

The top three images are all likely to be reflections from security chains that are not properly fixed (because there are no lamps to fix them to in those positions on the bar)

I think the source of all these glints are similar metallic reflections but I agree there could be a hole in the curtain, or even a gap where the two halves of the curtain should meet that might account for the one nearest to you