emmc.bin is indeed for regional content only but if you have a serious issue and a rootfs flash is not helping it could be there is some content stored on your MyDocs partition that is causing an issue... A full flash solves it... Actually I would have preferred a re-installation of some packages to try to get to the bottom of it but since you already had re-flashed rootfs.bin so many times it was better to do one reflash and fix it