Just to put this here, for future explorations on non-destructive approaches:
Red Team vs. Blue Team: A Real-World Hardware Trojan Detection Case Study Across Four Modern CMOS Technology Generations by Puschner et al, linked above, mention the following:
“New non-invasive scanning methods based on X-Rays [17] seem more promising for the future
than the lengthy process of delayering and imaging the chip. These non-invasive techniques are potentially able to scan all metal layers and provide a 3D-image of the entire routing without destroying the device, but the research on this subject is still at an early stage.”