Is very unlikely something like this can be caused by a scenery, ntdll.dll it's a very low level OS module, that deals with basic kernel functions, like memory allocation, task scheduling, etc. Problems in sceneries usually cause crashes in FS9 graphic modules, like G2D.DLL or G3D.DLL, rather than low-level OS modules like ntdll.dll.
It's probably something like an Out of memory, or something similar. And, fact is happened at 20-30 nm from PHNL, finally confirm it doesn't have anything to do with the scenery because, the scenery loading range for almost all objects at PHNL is set to exactly 10 nm. Outside that range, nothing is loaded.
Have you patched your FS9.EXE to allow >2GB ? (of course, it's meaningful if you *have* more than 2GB of RAM, and under XP you need to patch the boot.ini file as well)