Stalking Supply wagon issue

[Big Gigantic Butt]

has been working good so far though recently i sent it with aleifr to caer ligualid and he didn't come back for longer than usual, then the city got sacked (it was mine, then another army took it) so dunno if that's what did it, or he was never coming back in the first place. but aliefr is AWOL now lol.  will wait a few months i think that's the max time for them to come back if something goes wrong and if something really went wrong i'll use savegame editor

i wonder if the wagon gets attacked what happens, haven't seen it yet. maybe a lord got him and he's in a dungeon somewhere. notes says he's trying to reach me but whereabouts unknown
EDIT:
he came back

 

[gdwitt]

There's a long script for the wagon getting attacked and lost.

There should be a warning and a way to rescue it.
That's too much for me to do with what I know.
It's one of the issues that frequent saves helps.
When I fixed the script, I ran about 100 tests.
I lost the wagon twice even though I am always sitting right next to the city.
It does happen randomly and I need to figure out where the code is that controls that.