What do you mean with this? "Same error here and resolved by connecting the box to an USB2.0 port. "
You were able to install the MXIII-C_202L1 with the USB Burning Tool ?
Or you were able to install the LibreELEC from USB2? (because none of the two box USB are usb2.)
You are shure that your box is this one MXIII-C_V1.2_20160419 ? Because non one was able to solve the issues with these boxes yet.