Samsung UN50H6203AF no image issue troubleshooting

In the past month we've seen a few units of Samsung UN50H6203AF in the shop with the same issue - TV starts up, backlight is there, but there's no image on the screen even though the T-CON LEDs are on in blue and it appears as if the T-CON is just fine.

Testing output voltage to the LCD panel shows that at first it gets a spike of proper voltage, but then goes down to 0.

Then we actually ended up "repairing" (though frankly I still don't dare call this repair) one of them with another one currently waiting. The "repair" is something we've done before as a last resort by means of losing portion of the panel and re-purposing the TV for digital advertising or other situation where one could go with missing an inch or so of the display.