That's a really good question even if the answer is very likely no.
Considering it could take anywhere up to 100,000 years plus to for a resultiung planetary nebula be visible accross the entire galaxy, even if Betelgeuse went supernova tomorrow, the light from the event and subsequent remnants would have only gone a few 10s of systems over in every direction by the time the ED universe rolls around. Then considering that computing what time dilation you could see from any particular point on the Galmap becomes a near infinite calculation even in a heavily simplified mathematical model I'd say certainly no.
The only way you could simulate supernova in ED is to have light from it instantaneous which would be weird, and would be dynamic in a way that very distant objects really aren't. For example the last recorded supernova in Milky Way was in 1604, Kepler's star. The actual supernova occurred some 20,000 years before that though according to it's distance from us. Now there could have been other supernovas since, or even before, that happened further away and we still see the star as it was.
In fact, Betelgeuse could have already gone supernova, at any time in the last 500 years or so and we'd still not see it yet. (And I spend a few moments looking at that star every time I can see it, just in case.. y'know)
And then of course what you should be thinking is; hold on a minute, what do these nebulas and remnants actually look like now? because we don't know do we. So the Galmap isn't even a freeze frame of our galaxy (which when you really look into Relativity and so on is neither a plausible nor possible thing) it's just a freeze frame of our perpsective from within it.
And if we ever want to see 'realism' in a simulation of galaxies in this sense, I think we'll be waiting for Elite 13 Quantum Revenge in roughly the year 3305
That's not to say you couldn't make some sort of gameplay feature out of a completely unrealistic representation of it. Why not? I'm sceptical because to make it a gameplay feature it would have to be happening at an extreme rate, like 1 a week, and it would need to be a newly generated and injected system that didn't exist before to avoid just slowly deleting the entire galaxy. Could be done I guess.