[1.1.2624] Inprisoned pawn dies on unloaded enemy camp map

[Paknoda]

I write this up again, because I got some more details, which narrow the problem down.

I got a quest to rescue an imprisoned pawn, whom I haven't encountered before in my playthrough (Breaking <pawns name> out). The quest asks to rescue the imprisoned pawn, by fighting the guards in the enemy camp side and freeing the pawn.

The quest itself is active for 15 days but the pawn in question dies on the same day the quest is received at 20h. I know this, because the pawn is the fiance of one of my colonists and by viewing the social tab one can see the switch from the status slave to dead, which promptly results in a mood debuff for the fiance in my colony.
The quest itslef stays active, but the pawn imprisoned on the enemey map is another as the stated one.

I play on a world with the overall temperature being very high, so my assumption is, that the imprisoned pawn dies of heatstroke.

I assumed that "unencounterd" pawns on "unloaded" maps are kind of protected from the weather and I am a little confused that the stated pawn of a rescue mission can die before the quest itself ends. One would assume that the expiring time on the quest itself would be the indicator.

[ison]

It's weird, could you please upload the savefile so we can check it?