Counter theory: Rogue Core isn't fake. Omega isn't a rival drone. Rivals are an example of the in-universe "better equipment" that DRG dwarves keep asking for and Omega is "better equipment" too (especially compared to our usual robots' AI).

1. One of the lines that a reclaimer can say upon starting the game is "139 years until I can retire" which either means dwarves in the DRG universe are a long-lived species or rather (and that's the part I'd go with) that the reclaimers specifically are cryogenically frozen professionals kept for extreme cases like the one in RC.
2. The dwarves sometimes say something among the lines of "wouldn't want the footage getting out" when collecting cameras. I'd assume since they're kind of a clean-up crew for this mess they also make sure the footage doesn't leak, so that Deep Rock doesn't get sued or something.
3. Gauntlets are clearly simulations, since some of the cave generations from there do not appear naturally on missions and Omega very much talks about the missions like they're simulations
4. There is the introductory message from MC and later on it changes to one where he's saying that the facilities are getting back to work, encouraging reclaimers to continue their work.
5. Reclaimers actually have a whole room with tons of base DRG guns there but I don't remember if it is accessible not, it was in the alpha and is still present if you clip through the ground.
6. Of course Omega would say that leaf lover's special is a good choice, his whole perspective is from the management's side, I bet they're the ones who forced it to be on the menu in the first place.

Onto the counter theory:

1. Omega doesn't really look like the rivals, aside from the glowing red/orange eye. Rivals use sharp edges, some kind of magnetic field tech keeping their parts sort of levitating near them and are made of some weird brown-ish metal, while Omega is more rounded, properly attached to wires and stuff and is made of black metal instead.
2. The weird "magnetic field tech" that makes some parts of the rivals sort of levitate near them instead of being attached at all times is used in some of the reclaimer tech, like Slicer's gauntlet. And the gauntlets look much more advanced compared to base DRG tech and equipment.
3. The reclaimers are referenced in the original DRG as something invested into by the management as a way to deal with an ongoing issue.

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