I don't know site u mention, I'm not trying to lead you on any merry dance, I've pointed out a lonrisun image that was linked to you. I try to explain the differences in the images, my disadvantage I'm trying to help online,pointing out possibilities of cause, tbh he could as I said have ruined nand flash chip, it could have bricked,it could just need reflashing. I tried to explain why a lonrisun clone differs, from sunray, they can both use a genuine image, but the image kernel for the lonrisun is 'stepped back' so to speak, to allow its use on receiver , hence an 'unmodified kernel image ' won't flash. Whichever of these 3 causes end up being issue, you've taken a step, by identifying the brand & version v4 of image, so you have flash to investigate, failing that, u have tool wullboy linked for recovery, lastly you have the replace nand chip, which might be cost prohibitive ,labour wise. I hope it works out for you