It shows a 4500 radius, and yet it hits on a 13,500 radius.
Not sure what your seeing, but it looks okay to me:
I fought against an eldar corsair, and i saw a small circle that i avoided with all my ships. Then all my shields were gone. So if this is not the case then maybe he modified the game?
I believe this is a problem for some of the factions, I've seen this happen for all eldar