If she didn't drink while in the bath, another way you can encourage her to drink is to gently dribble water over her head, like under gently running tap. (it mimics
rain, which snakes instinctively drink from)
I only use hot water to warm feeders too, but then again, I don't currently have any snakes that are that fussy. I agree- the tiny bit of extra hydration from soaking
prey items in warm water could only be a plus.