Hi Erik,
This was a while ago now but if I recall, running the RAWs though RC produced weird warping effects however when we processed the RAWs in CaptureOne, setting to generic the results we better in RC. This suggests that even off, the distortion information automatically applied in camera is stored in the meta and used by RC.
Like I said though, this was a while ago so it may have been fixed by now or originally caused by some human error on my part as I don’t recall others with the same issue.
Cheers for posting though.