It depends. If the the problem is that the eMMC went read only during the update because the eMMC was already corrupted, then this would help. If the problem is something else, it won't. Is UDPIH still working (purple LED). Also if the problem is a read only emmc, it can still be read and transferred to an sd card, so it could be fixable without a backup.
It depends on what is causing the error, there are mainly two problems, which can both lead to a 160-0103 error. Either a CBHC brick, then you will see in the COld Boot Title menu in the recovery that that title is wrong and you can fix it there.
If it is caused by a bad eMMC chip (we could see that in the logs, which you can dump trough the recovery menu) then this project would be right for you.
If it is a different error message, then this also wouldn't help.
As long as you can boot the recovery with UDPIH we should be able to fix it without a backup.
You can't use a backup of a different wii u, as each one has it's own encryption key. The only thoing you could use it for is to extract single files to replace broken ones on the other. But you can also get most of the files from the NUS.