Your first ball hit to the edge of the green, you may have used your ball durability, hence the ball replaced with another.
Your second ball hit into the, as you put it “deep brush” thats happened to everyone no doubt, but deep brush gives it away, i’ve lost a ball on the 10th @ Bethpage, hit left, “lost ball” You can loose a ball off the 10th at Olympic, hit the trees, it drops down in to the rough and a lost ball.
Certainly some of the lost ball issues are bizzare.