OK, that seems to confirm that there is something wrong with avisynth or the original BD (or 3D MKV).
If you use the 32-bit version of x264 (not x265), avs2yuv is not necessary and therefore not used. x264 loads the avisynth script directly. It might be a good idea to test that with the same source, as we will know if avs2yuv is the culprit.
Also, you can try to use another version of avs2yuv. There are 4 versions
here. Of course, the 64-bit version is not suitable. The version distributed with BD3D2MK3D is 0.24, but its size is 52KB. All komisar builds have a different size, so try the 3 32-bit versions.
I note also that ntdll.dll is involved in the crash. Perhaps it is the real culprit. Could it be caused by a recent M$ update ? What version of Windows do you use ?