I don't understand why Ford did not just put the LLM on a PiP.

Of course in that order!

Step 3: Rehire key personnel at lower cost than whomever was fired in Step 1. Step 4: Take credit for cost reductions . . . and give yourself a raise!

Alternatively:

Step 1: 30 minute conversation with AI on how to use AI. Step 2: fire everyone.