If it were me, I would be (very) cautiously optimistic. (What I started to type first was "hooray?") I agree with Marie in that more will be revealed, time will tell. Maybe it will be helpful for him to have a motivator, I don't know. All you can do is to take it day by day and keep taking care of you and the kids.
Side question...IF something were to happen and he was not sober at the time of the trip, would you be able to or be okay with taking the kids & going without him?