I'm just rotting the dev warnings about this chip vendor for emmc, and porting android on them. There must be thread about this precise issue, I didn't follow them. Fell free to look for them.wait wut?
i dont think that wpinternals would be wrong about the samsung chip in the info...
moreover ive only seen hynix and samsung in these lumias, i dont think that there is any other vendor out there that makes the chips for THESE SPECIFIC models... ive seen toshiba in the higher 1520 models.
most rare ones are the micron chips...ive only seen 1 lumia that had that chip.
also, another thing i've seen is the problems with the drivers... not having proper drivers also results in failures, so have a check on that too
Anyways dev recommand not to go on with installation of your emmc is from Samsung, that is clear for them. But you can always try, but do know that you can hard brick your phone