[Jon Hensen]"Think there is any recourse to troubleshoot, or am I stuck with defunct hardware?"
You are not stuck. Take it to an Apple Store and they will fix it for you. You may even be able to mail it to them. They have refurbish program where for $250 USD they will take your MacBook Pro and completely refurbish it fixing anything that is wrong. It takes about a week. It may even be free if it's part of a recall.
I just had them do it for a MacBook Pro that I had where the screen was showing strange lines. They gave me a new display, the hard drive showed errors so they replaced it with a new one, the bottom had a rubber foot missing and was scratched so they replaced that too, there was a bad memory chip so that got replaced, ...overall they made 5 repairs, it came back looking and working like new and it only cost $250 USD. Well worth the money to me.