re your previous post: gar, irritating inconsistency.
i found another formation with dormant enemies: Chaser + Trapper x3. i hacked Chaser's counterattack script so all it had was "If monster is in formation #122 / If monster is dead/ Monsters #1-6 are killed, diagonally [i.e. the undead SrBehemoth fade]". surprisingly, the animation appeared perfectly fine.
then i noticed that unlike dead SrBehemoth, Chaser is in the very first slot of its formation, and all 3 Trappers in later slots. so i tweaked the formation to move a Trapper from Slot #3 to Slot #1, and Chaser from #1 to #2.
sure enough, its fade animation was replaced with the pause followed by the quick disappear (i assume that's what you saw with SrBehemoths?).
i was gonna say you could switch living and undead SrBehemoths between slots #1 and #2 in both formations #424 and #452, and avoid having to edit the undead's script. but living SrBehemoth has a position-dependent command in its script, so no go, as you'd have to edit that one instead. motherfucker.
besides, i'd be uncomfortable relying on monster formation positioning to avoid the animation bug. seems too damned arbitrary. gives me nightmares about the Cranes.