From our experience, the Interactive Intelligence IC User Tools pose a few issues.
1- We could never get the main package to install on the PC if no one is logged in. That necessitaed that we have to run the tools at next login so that it starts up the next time a user logs in.
2- The second problem we saw was from installing the package off of the server. This posed some issues in that the install adds some components that necessitate restarting the network connection. The best way we found was to copy all the install files locally, then run the installs.
3 - I don't think that the /qn will work for this package (at least it never did for us). We had to use a /qr (which I believe is what the IC User Tool documents says to use).
As for your batch file, I would make two changes. First use the /qr and see if that fixes things. Second, if possible try to cache the installer files and all supporting files locally first, then run them from the local cache.
You can just include the patch file as a required additional file and then just use the path to the sdmcache folder "%LD_CLIENT_DIR%\sdmcache\<path to software cache>"
/i /norestart /log "C:\ICUserApps_64bit_patch.log" PATCH="%LD_CLIENT_DIR%\sdmcache\ldlogon\SoftwareStore\IC4SU5\ICUserApps_64bit_SU5.msp" ICSERVERNAME="ICSERVER" /qb