I think making your expectations clear about the Dogs would be a perfectly ok exception to the overall "not initiating" strategy.
Your understanding is that you two agreed the dogs should stay together, and you interpret that as meaning the dogs will be staying at the house, and if she feels differently that is something you two will need to discuss.
Doesn't need to come across as mean or punitive; given the situation, I would set that boundary ahead of time.
Me, WW - Upper 30s BD - Apr 1 2016 EA - Apr 7 2016 (discovered; ongoing for months; did not confront right away) Confronted wife about EA - May 17 Wife sent NC email to OM - July 11