I misread, I thought that was the correction, which is why I got confused since it was mostly the same (I'd changed a few things since posting to check), my bad, sorry
That said, that was the very first thing I tried, and it still doesn't work.
itemLeafDetonator = new ItemLeafDetonator().setUnlocalizedName("itemLeafDetonator").setTextureName("tfm:itemLeafDetonator").setCreativeTab(tabTerraformingMod);
item.ItemLeafDetonator.name=Leaf Detonator