This usually happens because the RAW sensor channels clip unevenly, and after white balance the clipped highlights can shift toward magenta/pink instead of neutral white. It’s not necessarily a bad file; it’s how the clipped data is being rendered.

In darktable, the fix is typically in the Highlight Reconstruction module. Use it to discard or rebuild the clipped color information in the highlights. In particular:

• adjust the clipping setting to suppress the magenta cast
• try a reconstruction mode such as Reconstruct in LCh to preserve a more natural highlight transition
• if needed, use blending so the correction only affects the problem area

RawTherapee likely applies different default highlight handling, which is why the same image can look fine there without extra work.

So the cause is clipped highlight color data after white balance, and the practical fix in darktable is highlight reconstruction rather than changing color profiles or tone mapping.