Hi,
After 3 hours of struggling here is the result
1) if scene is rendered with AI Up-Sampler C4D native denoiser is processed but not effects on final image result
2) if AI up-sampling checkbox is unchecked, same problem occurs. Up-sampling mode has to be "no up sampling" as well.
3) mainly if Up-sampling mode is "no up sampling", denoiser is being processed and effects final image.
C4D 23.110
Octane 2020.2.4-R2
ACES workflow