Yes. And its worth noting, those phones were in an area with low cell signal. Maggie wasn't as prolific a phone user, and Paul's phone had 2% battery left. If they had their phones in their pockets and hands busy for a few minutes (catching and putting Bubba in the kennel, putting the chicken away, feeding, watering dogs, etc), there's more than enough room for the TOD to be later.

And if the killer was indeed known to them but was not Alex, they could have talked for 5-10 more minutes before things went murdery. Maybe they talked about the boat accident lawsuit before things escalated. Maybe they were threatened with a shotgun and Maggie and Paul stayed calm while Paul worked his way to where he left his rifle.

Pleeeeenty of room for reasonable doubt.