1. Technically, he can’t pasul baked matzos, but he can bake matzos shelo lishmah.
2. I agree that technically it’s next to impossible to pull it off, as I posted earlier. I’m looking at this from a theoretical perspective, as yekke2 suggested.
3. You might be right, b’dieved (l’chatchilah, the bakeries are makpid to constantly say “l’shem matzas mitzvah), but not if he had specific intention for it to be shelo lishmah.
4. I wasn’t disputing this point, but you seemed to be inferring that the acceptance of machine matzah, at least by some authorities, indicates that there’s no need for lishmah, which is not the case.