The best way to get this one is to use grenades, that's the method I used and I got it the first time I played this map. Since this level has a lot of places where the grenades will abruptly halt their bouncing on the floor, it works great. If you're great at sticking then try for that, but if not just weaken someone and let them attack you and before you die just let one of your 'nades drop towards the enemy, achieve this twice and you'll be 25G richer.
I got Multi Flag when I got this map so I had plenty of time. Haha and everyone quit except for one guy, good times.