The existence of the Super-earth was not directly observed, but was instead inferred by the gravitational lensing of all the democracy[0] being spread in a sphere around the planet.
We know that, due to the lack of observable galactic civilizations, if there is a Space War For Democracy, it is a Shadow War [0]. Perhaps with one exception [1].
[0] https://helldivers.fandom.com/wiki/Super_Earth