Had the same problem happen to me. My huskies tried to haul something that was outside their allowed area and as a result ran right into the middle of a group of centipedes with predictably catastrophic results (for one of them).
I've been able to reproduce it consistently in the attached save. If you follow Killer around at max speed she will eventually (usually under 1 min) try to haul something outside the home area despite being restricted to it.

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I've been able to reproduce it consistently in the attached save. If you follow Killer around at max speed she will eventually (usually under 1 min) try to haul something outside the home area despite being restricted to it.

[attachment deleted due to age]