I speak under correction but didnt'nt Stephen Hawkings showed (mathematically) that certain particles can escape a 'black hole'? Given that we actually work (rather) with Mitchel stars is it still possible for some particles/radiation to escape the 'super' gravity?
If the elysium medium around such an object is extremely dense then I would guess it is simply a matter of the photons/em waves slowing down where they take a very long time to escape or cannot propagate bacause of friction of the medium - extreme case of tired light.
Rudolf