This is a bad video, but the red spot 30 s in is definitely on the south side of the collapsed top of the No. 1 reactor (you see the red top and white side girders and you can identify fallen girders on the last two photos here). It's hard to tell what it is, but would it be anything red hot, it would have shown as an extreme peak on the thermal images.

All this wild guesswork starts to remind me of 9/11 'theories'...

_{*Lunatic*, n.
One whose delusions are out of fashion.}