Soft units may disperse at about 75% (IIRC) damaged.
It
may be that for some reason, some casualty messages aren't being logged in the replay. Replay has always been "spotty" since SSI introduced it in SP2. It does drop some messages.
In SP1, there was no replay whatsoever. You got your PBEM turn back from your opponent and were left wondering "what exactly blew up my Tigers"???.
In SP2, they introduced the replay for those fortunate to have IIRC, 4MB of RAM, may have been 8. But it only logged firing. Some retreats and so fort seem to sometimes slip by it.
The replay was what prompted Don and I to produce the original SP2WW2 hack, since we wanted a WW2 game that had a useful PBEM replay and SSI weren't interested in revisiting SP1.
When we got hold of the actual code to develop I added some sighting events so that units advancing across the field of view were added to the replay. Previously, if nobody fired, then units could parade across a front and hide up out of LOS, and you would have no idea of that happening. Now you do get a hint!

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I also added non-reporting of messages on unspotted things showing up in the game (and thus the PBEM log). Previously some messages used to play for things that were hit or destroyed by collateral damage, even if you as the firer had not yet seen them.
The replay also does not properly log some events that use animations - such as cluster munitions in MBT as the classic example. If you have fast animations ON, it can miss these. But watching every shell of a bombardment gets tedious!. (I think with fast arty on you get one of the shell burst, if non-cluster?)
Also, but probably not the case here, there is only a certain amount of memory dedicated to the replay. I think that events outside the buffer limit don't get logged either. That only happens on larger games I would say - though that has never been investigated fully. (It may be the case that events rotate back to the front of the buffer, thus overwriting earlier ones). This game is small, so should not have any such problems.
So the replay is a heck of a lot better than for SP1. Its not perfect, but is workable. The Sp1 no replay was totally unworkable, unless players agreed to send a written narrative of what happened each and every turn, along with the turn itself!.
I may take a look at how it handles fast animations (fast arty) in the future, as the non-show of cluster munitions seems related to that. It may also be why some other events don't log on the replay.
(The save game you sent is of course useless for debugging the events of the firing and logging of same that happened in your opponent's turn. Those had all been and gone by the save point.)
Which begs the question - did you have "Fast Artillery" set ON?.