Quote: "I do of course realise I could animate models myself but would rather spend my time developing other aspects of the game"
There are things you could do and use the Dark Matter 2 and 3 models, but that would take some work on your part. One method involves first 'cutting' the model up at joint points to create individual limbs in a 3d modeling program, then linking the limbs in a proper hierarchy. Depending on the 3d modeling program, you could use the animation keys of the original bone rotations to match to the limb transformation keys. This, in theory, would allow you to use any type of model with DBC as long as you prepare the hierarchy properly in the 3d program (and the 3d program can export hierarchical animation in Direct X).
And of course you could change the animation of Dark Matter 1 models using Robert The Robots free lightning limbs animation utility.
Enjoy your day.