The information sounds quite contradictory to me. Yes, the temperature is below zero ("corrections to DA should be applied"), and yes, the OAT is higher than the value mentioned in the note ("no temperature corrections in the final approach segment (which includes the DA) are necessary"). So, should I correct the DA or not?
Why do you say the final approach segment
includes the DA? I think this assumption is the source of the perceived contradiction. Yes, we always correct for DA/MDA when below zero regardless of actual minimum temperature stated in the notes. A thousand feet up you have a lot of buffer (not going to hit any terrain) whereas closer to the aerodrome, the same temperature error is unacceptable due to proximity of the terrain (The runway).