By the way, not sure if this needs a seperate
Memory Manipulation resistance, but the fact that memories are stored within the spirit body IN ADDITION to the brain of the material body, should make memory manipulation impossible unless it's BOTH spiritual and biological. Even worse when it's 3 layers for those with perfect memory who on top of it store them in their souls as well.
Rimuru's non-physical body is even more complex with his homogen cells-structure. In LN vol. 1 he asks if his memories are like a RAID-setup for computers, and Great Sage's answer was "close enough".