Not sure if it’s well known yet, or not, but the new “Pixel Sniper” title can be cheesed using a bot and vehicles in Casuals.
Randomly got the achievement by downing a bot that was on a roof at Quarry. Couldn’t be bothered clambering up there to finish it so left it to bleed out and hopped in an LTV to carry on my Easter Egg.
I’d driven over 500m when I got the ping for the elim and the title achievement popped on screen. So it looks like you only have to be 500m away from them at the time of the kill counting, not necessarily at the point of downing them.