I just resolved the issue. I had to download the ffmpeg-win-2.2.2.exe to another computer, copy it to a thumb drive, copy it to the PC that said the setup files were corrupted and then it executed without any issues.
ffmpeg-win-2.2.2.exe download
Right-click on "ffmpeg-win-2.2.2.exe" and select "Save link as" to download this .exe file. Simply run "ffmpeg-win-2.2.2.exe" installer and complete the installation, FFmpeg Library will be automatically installed and configured in Audacity. If it doesn't work, try the ZIP option and manually locate FFmpeg in Audacity as follows.
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