out of morbid curiosity.... how long did it take to ssh into and fix all of those servers? I imagine even automating a fix (if possible) would still take a good amount of time.
The way I built my app was that I could install it cleanly via a curl | bash.
So, I just had a simple shell script that iterated through the list of IP addresses (from the DHCP leases), ran curl | bash and that cleaned up the mess pretty quickly.