There is no SimpleDSCSModManager Executable.

[NeonGreenYogurt]

The instructions say you can run it in one of two ways, but the first option isn't an option because there is no executable.
The 2nd option is sus because you say there is a literal virus involved.

[SydMontague]

If you don't want to build the mod manager manually, use the prebuilt binary provided in the releases tab: https://github.com/Pherakki/SimpleDSCSModManager/releases

There is also no virus involved. It's just that anti-virus software sometimes mistakes things for viruses when they're not.

[NeonGreenYogurt]

I see! Thank you!