An ace on hole 6 is a ballsy ballsy ballsy shot. Like you say, the basket sits on a man-made beach no more than 10 feet from the edge of the lake. The only way to approach that basket in air for the ace is for it to be fading/hyzering toward the water (assuming righty backhand which is what J-Bird threw). There's no straight line or "safe" play on that ace run. If the shot misses the basket, he's looking at a guaranteed 3 because that disc isn't not landing in the water.
J-Bird has the arm to get it there in the air with no doubt...wouldn't surprise me if it was a skip ace though. A lot more realistic of an approach if it hit short and skipped in than going in from the air. An impressive ace regardless though. Doubt anyone will duplicate that one anytime soon (pretty safe statement considering it's the first time in 10 years it's been done).