New try: I recompiled sedutil after booting linux-image-6.1.0-18-amd64 (git clone --branch s3-sleep-support https://github.com/badicsalex/sedutil.git). It made no difference, i.e., I still can't get the machine to fully wake up. (sedutil compiled at linux-image-6.1.0-18-amd64 still works fine with linux-image-6.1.0-13-amd64).