Blackmagic Raw is supported on the VA12G, but only for specific third party cameras:
Blackmagic RAW Supported Cameras:
Canon EOS C300 Mark II, Nikon Z 6, Nikon Z 7, Nikon Z 6II, Nikon Z 7II, Panasonic AU-EVA1, Panasonic LUMIX S1H, SIGMA fp
As you can see, the Ursa Mini Pro 12G (nor any BMD camera) is on the list. Select BMD cameras with BRaw ability can record the raw codec internally. BMD did make a Raw recorder for some of the Ursa Mini’s but it appears, it is no longer supported.
Cheers