Ok, on that second turbo, you definitely have a FOD issue going on as that much damage is definitely caused by something going through it.
Have you pulled your oil feed line off and cleaned it throughly?
Take the MAF sensor off again and check it again. There are round plastic clips that secure the screens to the MAF sensor. There should be 2-3 round clips and either 2 or 3 screens. I would be willing to bet, if you remove your intercooler and flush it, you will have particles and pieces come out of it. Those round clips are black plastic that snap into notches on the inside walls of the MAF sensor that secure the screens.
If you oil feed line is good to go and the oil drain line is also good to go, I'm suspecting FOD damage from the MAF sensor or something getting past your air filter.
If you noticed one of the screens was missing on your previous tear down, I'm betting that's the main cause of continued failure. If you can imagine the light weight screen material getting chomped and blended by the compressor wheel under WOT, then when you let off the gas under WOT, the non digested pieces got blown back into your MAF and air filter. Odds are, those sharp particle pieces got stuck in the rubber of the air filter and eventually flew back into your new turbo over time and repeated the blending / chomping process.
The car just wants to eat, that's all. It's not possessed.

Yeah, I edited out the small creature getting injested comment. LOL
Just a few more thoughts.
Patrick