Your original question mentioned going back to the R3d’s, so I included that idea in my answer. If you want to do that, then you are obviously going to need the camera raws. If your Avid was working at low res, and you want to stay in mxf, then you would need the camera raws to get avid up to high res mxf before sending to Resolve…or you could use Resolve to read the camera raws, and skip uprezzing in Avid. Depends on your desired workflow and perhaps desired finishing output.
If your Avid is already at High quality MXF, and that is what you want for your final quality, then you wouldn’t need the raws.
No correct or incorrect answer…just different workflows.
Glenn