So far, all races that encounter markers do so because they reach a point in their civilization where they can't sustain their growth. A way to stop the entropic forces that are building thanks to sentient species running around and consuming the universe's resources. Whatever energy a marker emits is able to preserve life absorbed within whatever the moons become. Personally, I think Markers are shitty way of preventing the heat death of the universe. We don't know why Moons need to be formed. Waiting for life to become sentient and create more copies for convergence. We can assume black markers are thrust in the direction of life by the Brethren Moons or their creators, and somehow crash into planets. We don't have a concrete origin for markers. Unfortunately, or fortunately, the SCAF destroyed all meaningful research on markers, so when EarthGov took over, they didn't have enough information to make new markers.

I don't think there was a full blown Necromorph outbreak at the discovery site of the Black Marker, but I believe Altman and the Unitards were affected by the Black Marker's psychosis and the SCAF/EarthGov wanted none of that shit. Similar to the recipe of a tootsie roll requiring a piece of the previous batch. As long as one marker exists, they all exist, hence why Unitards like the idea of living forever because Convergence binds them to a marker that 'can't die'.

It's possible all markers are an aggregation of energy from previous markers, so the SCAF used their copies to trace Tau Volantis.

The SCAF also thought they found the origins of the Marker on Tau Volantis, and well, they weren't necessarily wrong. I don't know if the SCAF encountered necromorphs, but I figure Kendra's reports on a marker's psychological influence comes from the SCAF records that weren't successfully purged in Scenario 5. The old governments of some 200 years ago shut him up and killed him to cover up the existence of the marker, but the Sovereign Colonies, or SCAF, managed to create the blueprints for three markers. He was a only researcher, but even after his assassination, the research on Marker energy got out and the Church of Unitards formed anyway. Michael Altman found it and wanted to spread the news of the Black Marker being a new energy source that would solve humanity's fleeting resources. The Black Marker crashed into the Yucatan Peninsula, specifically the Chicxulub crater that wiped out the dinosaurs. The original encounter with any marker by humanity happened on Earth.

Dead space brethren moon musc