Respectfully, space, by definition wouldn't be empty. Something moving thru something would lose energy. Hence the red shift.
Speaking of which, which way is this light moving? Something happening 7.5 billion light years ago would have been 7.5 billion years closer to us, hence the light would have passed us back then. Unless......unless the light we see is the light moving from the other side of the object directly away from us, and curved by the mass of the universe 360 degrees.
Impossible you say?
What other explanation would there be for a uniform cosmic background radiation coming from all directions at once?
IMHO
Bob