If there was write protection on eMMC all writes would fail, so partial write (7%) means there is probably an issue with the eMMC chips, or the power supply which causes instability during writes. It's a common issue with older and cheaper Android boxes due to age/wear on eMMC chips and the low-bin/low-quality components used.
7% restored means that some boot code (u-boot) exists on the box now and this should be enough to boot LE from SD card. We don't support installs to internal storage on random Android boxes so you will need to run LE from an SD anyway. Use the AMLGX Android "box" image with the toothpick method to hook into u-boot. You will need to experiment with different device-tree filenames in uEnv.ini to find something that works with your box. If the box has Gigabit Ethernet the S905D vero4k-plus dtb will probably work. If the box has 10/100 Ethernet the p212 dtb should work.