So the same neighbor whose tv I tried to fix, did fix, then broke while putting the bezel back on, bought a new Samsung DU7200 43 inch smart tv from Best Buy.
I helped her to get it working, we disabled the smart hub as that is a pain if you just want to use the two hdmi ports and not use any of the extra crap.
And that worked...until just after the 15 day best buy return policy...and she did not buy the extra coverage, and so was only covered by the Samsung warranty...well that process is horrible to get things fixed, and she gave up.
So I stepped in and worked through the repair process...and we got it working again, and she has a working tv again.
Things I learned, the samsung support chat sucks...those tech's are doing multiple chats with people at a time and so things that should take sub 20 min to diagnose....took almost 3 hrs while waiting for them to reply back with the next steps.....ie it took an hour for them to say 'power up the tv', and a second hour to 'power cycle to see if that fixes it'...then another 40 min to 'you need to open a repair ticket'.
So I did, and the tech came out, figured out it was the control board, replaced it, then we had to fight with one of the service page setting for the sound settings...in order for it to all work.
Once that was finally set after three other support phone calls, the tv is back to normal again, and she is able to use it.