I also consider the exploding D's that didn't stick. Like the various deaths in Cause and Effect, and the alternate dimensional one Riker was encharge of from the reality where the Borg had taken over the whole galaxy. I'd even add the one from Yestetday's Enterprise. It's a personal thing. When I think of the D, I think of it going up like the Fourth of July. I gets rammed in one of its nacelles by another ship, spins out of control, and poof. The Reliant gets its nacelle blown clean off, and nothing. Plus I will never get past it getting killed off by a single, very old Bird of Prey after only shooting back with one 2 second phaser burst and one torpedo. I know that's just bad writing, but in the end, I feel the D was squishy. But in the, it was utilized more than any other Enterprise, so naturally it experienced more, too.
Actually, I did review all the Enterprise D's destructions in alternate timelines and what not.
Time Squared seemed more related to that vortex thing than it did any of Geordi's engineering skill.
Yesterday's Enterprise Geordi was responsible for. That's 1.
Cause and Effect it blew up almost instantly after the Bozeman collided with the nacelle. Between that happening and Picard ordering abandon ship, there's not much Geordi could have done, he's off the hook here.
Timescape Geordi wasn't on board the Enterprise when it blew. Off the hook again.
Parallels we don't actually know if Geordi is still on board that Enterprise, the only ones we see are Riker and Worf. For all we know he could have been killed or assimilated, so I won't blame that on him.
AGT has the Enterprise being destroyed three times, but only one of them Geordi is responsible for, the 2370 one. He had not yet arrived on board the 2364 one, and though he was on board the 2395 one he wasn't an engineer, so I won't blame him for that. Still, the 2370 does count, so he's now at 2.
Generations of course not only fell under his responsibility, the Duras sisters were seeing through his eyes. Which brings our count to 3.
Compared to the other engineers:
Scotty lost his ship once, but that was through self-destruct.
O'Brien is tricky. Technically you could say twice, but one was the station, and the other the Defiant, so technically you could say once and it is still true from a certain point of view.
Of Voyager's many destructions, B'Elanna was only really responsible for one of them, and she quite literally was given it was the result of the quantum slipstream drive she had installed.
Trip is an interesting situation. When the NX-01 was destroyed in Twilight, he was no longer the engineer but was in fact captain, so yeah, he's still responsible. Then again, he was already dead, and the actual destruction was because of Archer, T'Pol and Phlox messing with the warp core.