Do undead NPC's always flee?

[strugglegenerator]

I thought all undead mobs never flee. However, I've found that a handful of undead mobs in Lower Guk are fleeing.

I was able to find those specific mobs (a_kor_ghoul_wizard) in the database, and sure enough, they are not set to flee. These include:
66144 - a_kor_ghoul_wizard
66141 - a_kor_ghoul_wizard
66122 - a_kor_ghoul_wizard
66001 - a_kor_ghoul_wizard

Is this just an error or do these 4 undead frogs in lower guk simply not flee by design?

I did notice that the value for Magical Attack (10,1) was entered twice in the Special Abilities formula:
10,1^23,1^10,1^42,1

I'm guessing this is a typo and that a value of 21,1(immune to fleeing) should have been used where the duplicate 10,1 is.

It's a simple enough fix for me to add 21,1 but I'm curious if anyone knows if this is classic or not.