I'm not a mower EFI xpert. I would stop buying new parts and TEST what you already have. All those new parts are suspect till you confirm they actually work.
From what you wrote, I would guess you still have some trash in the fuel system.
Was the fuel can an old style with maybe an open top or open spout? If so probably had a bunch of trash/water in the bottom of the fuel can. I would get a new style spout or new can. Fuel stays fresher and keeps most of the dirt out.
I would remove the fuel line AT the injector. Key on should fire the fuel pump. Drain a bunch of fuel into a glass jar. Should have a forceful flow and hopefully no trash/water. Flush out all injector lines closest to the injector as possible.