Silently uninstall setup.exe (Installshield)

[namahs]

I apologize if this has already been covered but I could not find anything using search.

My question is there a way to silently uninstall a setup.exe ? In my workplace, we normally use msi package to deploy the applications so they are easier to manage. Whatever that doesn't come with an msi file, we usually repackage using Wise.. but I am having trouble repacking this setup.exe file.

Their support said they do not have an .msi file, and for me to use the setup.exe -r and then copy the setup.iss in the folder and install it using the setup.exe -s command. My question is.. after deploying it to 100 users, I don't want to manually go to their computers to uninstall it. If it was msi, I would just use the msiexec /uninstall command. Any feedback would be greatly appreciated.