I don't think LE would ever declare someone deceased based only on a hit of a dog at a scene. They may think it, they may believe it, they may even talk about it among themselves as they review the case at headquarters, but publicly make such a statement? No way. They would need and want more information before declaring someone to be deceased.
They might instead use phrases like, "in grave danger," or "at risk," which we've seen LE use in other cases.
That in no way diminishes the 'hit' by one of the dogs at the Celis home. I personally think the hit of a spot in the house was by the cadaver dog. A bloodhound would be following a scent trail, not a single spot.
This reminds me of the Lisa Irwin situation, as well as the Madeline McCann case. Dogs hit in both of those cases and police have not declared either of those two dead (though they obviously suspect they are).
U
Until LE says something more definitive, which they likely won't until an arrest, I'm sticking with the one thing I know I can count on. The dogs & their training & their super-sensitive noses! If a well-trained dog alerted, it's for a reason.