Bizarre!!! OK this is what just happened to me...
I had won 3 consecutive all-ins in my last game but then went on to get knocked out by another reckless all-in attempt with crap cards (that was a few minutes later you understand), I clicked on "deal a new game" but then I immediately ALT+Tabbed out of the game to make the post above and browse these forums (I ALT+Tabbed just as the first player chucked the first bundle of $10,000 on the table). So after I finished browsing and posting, I went back into the game for some more attempts at this achievement. Where is this leading, you ask? Well the instant I went back into the game, a popup appeared "
Steam achievement unlocked: Down to the Green" !!! I mean wtf?! I guess I can't complain now that I have it, but this was one seriously delayed achievement which seems to have been bestowed upon me almost at random

Oh well, hopefully this may be of some help to others having issues with this achievement...
PS. The first 2 of my all-ins were immediate all-ins before the flop and was my first action in the round, where all the other players folded after that (so I gained very little money from those). My 3rd all-in was called by Max and it went down to the wire, though I got lucky on the turn and it knocked him out. This was all at "Normal" difficulty.