If you are installing the desktop version of DDM, you will be subject to Windows UAC. It is not DDM that requires permission to install itself, it is Windows that requires permission to install DDM. To circumvent that UAC permission prompt, install the program with admin privileges. I'm not all that familiar with InTune, but I believe if you want to install a Win32 desktop app with it, you need to first prep it with InTuneWinAppUtil, and then add it to InTune specifying the command-line parameters (/verysilent). One other possibility is to use the DDM package from the Windows Store, which doesn't require UAC since it is always already sandboxed.  Note that you should uninstall the Win32 desktop version of DDM first if you go this route.
We're also trying to automate the installation of DDM via Microsoft Intune app package definition. On specifying the installation command of ddmsetup1995.exe /silent, we saw on the target computer running the processes ddmsetup1995.exe and ddmsetup1995.tmp just hung 0% CPU for a very long time, and still there long after Intune considered the installation attempt failed. On trying out on my laptop the options /silent, /verysilent, /suppressmsgboxes, I found that no matter what it'd pop a UAC prompt for permission. Even if I approve that, it'll see show the regular installer wizard UI. Beyond UAC, I don't think those options work for the latest version installer? And given the UAC prompts, can DDM truly be installed automatically in the background?
DDM, automated installation, #2