1) Gobor was still existing, but only in one timeline red went there. 2) Yellow just lost his hat/ I’m too lazy to give him his hat 3) The four characters were blasted AWAY from the timeline, and the supernuke destroyed their timeline before Grey could. That’s how they survived.
Related links: https://scratch.mit.edu/projects/1259095897 https://scratch.mit.edu/projects/1252891842