This could also be explained as: matter thrown this way by the explosion and caught Regula's gravity well - the observed "expansion" of the planet could actually be just the Enterprise closing in on Regula - the glow is the same phenomenon we see in the presentation video.
As we pointed out, the script specifies it will look the same, only much bigger
"Gigantic cosmic scale".
The "Genesis Effect" WE SAW in its earliest experiments, now seems familiar on a gigantic, cosmic scale. The blinding flash at first, followed by the same tumbling turbulence of the miniature test. It is awesome.
Doing so much more, to the whole damn nebula, than we saw to the moon in the presentation video.