Geee, I honestly hope airplanes are not really built like this nowadays. Are you an informed insider on Boeing subcrontractors or are you just guessing ?
Informed insider from back in my days at Boeing.
I've seen a few instances where Boeing bought off on vendor acceptance testing without understanding the scope of the tests run or their limitations. A few acceptance test procedures were defined as "plug unit under test into ACME model 1000 tester, press the execute button and verify that the green 'pass' light illuminates". As a new engineer given the task of approving such a test, I got slapped down by Boeing management when I asked for the details on what the ACME 1000 actually measured. No time for that. The ATP needs to be approved to meed schedule.
I can only hope that tings have changed since I left. Subsequent evidence seems to indicate otherwise.