Watch out, I think its "runme.sh" (lowercased!) -- at least from quickly looking into the actual data.tar.gz . You might just create both RUNME.sh and runme.sh if in doubt.
Also, be aware that unless I'm completely wrong, this data.tar.gz will run inside the diags partition, so you may need to adapt the script to write to the main partition instead. But don't take my word for it. Probably it's best to look inside the data.tar.gz to understand its magic (I didn't thoroughly look inside, I never needed it anymore after having the SSH diags); otherwise the logic looks fine.
Oh, and beware: it's the Mayan goddess
of suicide. Somewhat fitting in this context
Cheers!
Update: Oh, and you may also want to copy the init.xargs somewhere (/mnt/us/init.xargs.broken?) before overwriting it, just to verify that it was indeed the culprit...