There are two problems with Locken's judgment that the battle host might deliberately expose him:
a) the GM can do this too, and aside from trusting in their integrity, there's simply no other option
b) the assassin doesn't create an exclusion zone around himself that no NPC can enter. If there's additional reasoning for why he moved there, then that's it, gg. Questions can only arise if an NPC made a completely pointless move straight at the assassin
A retreat in a straight line to heal is not a "completely pointless move straight at the assassin" meant to spite the player...
Ничто не возникает из ничего и ничто не пропадает бесследно.
Если где-то чего-то убудет, то в другом месте добавится.
(Закон сохранения).