If you've got kikuyu you are well south of me, I'm at Lat. 19. Had it in the yard in Adelaide, couldn't control it. It should be classed as noxious.
I'm on a little over a qtr. acre so very cost conscious. I bought a few L of 2,4-D years ago and at 1.5 mil/l it kills nut grass, but only to the first nut, stronger for a range of broad leaf weeds. I'm still using it. Its like DDT, effective but with a bad rap.
I'll look at the specs on that stuff but I suspect oxalis is tougher here in our bright sunlight.