According to @UniverseIce, Samsung developers are working on camera improvements for the Galaxy S23 smartphones, which also includes a fix for the HDR issue. May 2023 patch rollout has begun which could solve the vignetting problem.
After analyzing the error log shared by the user, in the reply, a Samsung executive explained that “the problem occurs due to a mix of negative EV input frames containing the same contour pattern, and applying LTM after HDR output will make the problem worse."
