Yes, but to be fair the reporting is incomplete because the Boeing-maintained records of the maintenance were incomplete in seemingly-deliberate ways. So... we just don't know. At least one, plausibly two bad guys there.
As far as I can make out, Spirit employees (probably with the knowledge and tacit approval of management, because that's the way these things usually go) found a loophole in the record system that allowed them to avoid triggering QA checks. Boeing has blame for creating a system with such a loophole, or failing to find it before it was used, but it was Spirit personnel who actually used it.
IIRC from one of the whistle-blower accounts, the main issue was that the Boeing computer system only had an option for fully removing the door, which wasn't done, only a partial removal to allow access to the parts needing work. There was then a disjoint between the Spirit work system and the Boeing one which resulted in someone saying "fuck it" and skipping it.
