Whether or not dwarves would have technology that ancient Greeks did is pretty far beyond the point. There are definitely way better ways of deciding whether something should go into the game. Are explosives dwarfy, or aren't they? Is a steam engine dwarfy, or isn't it?
Also, even though the Greeks never thought of Hero's engine as anything but a curiosity, it still wouldn't have taken that much lateral thinking to have made it reasonably practical. They knew of water wheels at least as early as 100 BC, and probably closer to 240 BC. A stationary steam "spigot" blowing on a wheel could've easily set them on the path to a practical steam turbine engine. Especially if they put two and two together with the Archimedes' screw and figured out that sealing the turbine in a housing increases efficiency enormously.
No one ever thought of that back then, but then none of them were dwarves either. Jets of high pressure, lethally hot steam (heated by magma, of course) being harnessed to open doors and grind cave wheat doesn't seem that un-dwarfy to me.
More like a player-controlled megaproject, rather than a ready-built (M)achine component, but still reasonably dwarfy.