If the bootloader is intact then you should be able to force a firmware update.
If the bootloader was included in the update you wer flashing at the time ..then I suspect it will stay bricked..
Removal of a memory chip and external flash being the only way to fix it ..
A it's not easy ..
B if the chip is BGA ...forget it ..
C you neeed the correct binary file ..or clone file from a working box.
D Cloning the chip is tricky and could brick both boxes.
E you need a suitable programmer and suitable TSOP base ..
F ...if you don't have the neccessay skills ...again ..forget it.