“All the 25fps footage is MOS montage footage. ”
conforming will not be a problem.
did you shoot RAW or ProRes?
if ProRes, then simply conform those camera originals before striking your edit media.
if RAW… well i don’t know about that.
could be you need to set the TC rate on those clips to “24@25”
talk to your post house,
a few simple tests might be in order
but i don’t see it being too much of a problem.
nick