I have thorn too, i just need to do the void crucible part and i hate PvP.

if you have atheons epilogue auto rifle(with stability perk), the comedian shotgun, and truth rocket launcher(all are void) it's very easy to get that 500. just play clash/salvage. you can revive there. read somewhere that the penalty won't count if you get revived. or do rumble, if you dont get kills/you are doing negative, just leave. it's freeforall so it's no big deal. hope this helps