I'm leaning that way, but just like the freaky coincedence of the fire at their former home on J Road. It's not always the spouse, right?
What IF - Ana had another love interest. Maybe that relationship was in crisis or she simply wanted to see him/her sooner than January 3rd. She makes up the work emergency as a cover to leave two days early. The problem with this scenerio is - someone said they saw her leave with suitcases, but LE says ring camera footage doesn't show a vehicle arriving to pick her up. So ...
It's my understanding there were only two adults in the home when Ana left. Brian says he was asleep, so that leaves the MIL? Unless it was one of the kids that saw her leave?
What if she's somewhere IN the house?