You think two minutes with a shovel is gonna save you every time? I've dug plenty of test holes that looked fine and then watched a pad sink anyway once real weight hit it, because the top few inches of dirt don't tell you what's going on two feet down. Soft ground isn't the only problem either, I've had crap settle on what looked like solid packed gravel after a rain. The outrigger pads themselves matter more than people want to admit, and no amount of poking the ground fixes a pad that's too small for the load. Leveling isn't wasted time if you're doing it right, the issue is guys cranking floats down into muck and calling it done. Probing the spot is a decent habit but treating it like a cure-all is how you get surprised.

What did the shop actually find when they pulled the file? I'm asking because there's a difference between a box that just clips the rail pressure signal and one that also messes with pulse width and timing. If yours was only touching the pressure sensor, then yeah, the ECM never sees real fuel pressure, so it can't pull fuel when it needs to and you get the P0087 plus a pump that's been running dry. Did they say if your injectors got hurt too, or just the pump? That $600 diagnostic might be the cheap part if the CP4 was eating itself the whole time. Curious what codes besides the 87 showed up in the history.