I have just hit one of these myself - sort of. Mine is SIMILar but not identical. CHECK OUT MY REPLAYS: BPB #5 - Hitting The Fairway - WATCH CAMERA 2
When I first saw YOUR replay, my question was how on earth did the the 3 foot tall long weeds on that little "island" not stop YOUR ball dead - or at the very least, dribble it out into the sand.
Instead of shedding any light, my own experience (if you view it) only deepens the mystery with a simlar question. "Why does the sand in which I initially landed suddenly appear to have the consistency of solid concrete? - enabling a BOUNCE of enough momentum to propel it through ANOTHER bounce through the ROUGH (rare in itself) - eventually landing in the fairway.
Enjoy My Replay, AtlantaCoaster