Unfortunately, I had level 3 glitch on me seven times so I had a lot of time to refine my fighting technique versus Destruction Worker. Everything you said is correct but I found a slightly easier way. After he gets done firing the five shots at you and begins shooting at crates to drop on you, run directly at him. You should hit the wall underneath him and just keep your LS pushed forward so you're continuously running into the wall. The crates won't be able to fall on you and when the last crate falls and drops the explosives, they will fall almost exactly where you need to place them. This makes the part with the wrecking ball A LOT shorter.
I'll let you know if I see anything else as I progress through the game (hopefully without glitches