I'd really not like to have a run in with the watch, however, I don't Admund would let the witch get away simply because she fell in the water. I don't really see a confrontation between us and her not attracting the authorities.
We have Hans the witch hunter, sent out on bounty by Graveland. Julian has evidence of her witchiness. She is wanted for a murder at the watch station. I think we have those things on our side.
Also, is Max on the Jetty with us? Don't want to leave him!