No, the supreme court didn't get it wrong. It should never have gotten there.
She also knew he didn't want the search, but is a legal resident there. She could have picked up the phone at any moment in time and told the police she was presently looking at a firearm she knew to be illegal and they would have had a warrant.
The fact that she agreed and knew full well there was evidence laying around indicates to a reasonable person the warrant was "enroute" and a forgone conclusion.
Several states have gone so far as to make laws that state it explicitly and have not been challenged. It is ludicrous to think the police should look for everyone that might be a legal resident and ask them. Once you agree with that, then you realize that any one person can agree has weight over any one person can not agree.
It becomes really a no brainer when you realize that a wife and a husband might be at odds over something illegal and dangerous. The police come for the public disturbance that was reported an hour ago. There is no obvious signs of a crime now. The wife says come in and see our son who is taped to the bed in the back room, and the husband says no.
Any one person has the right to consent to public safety amid a sea of "no"s.
If the police lie about the one person giving consent, they were going to lie about hearing a gun shot. This isn't going to be abused. Corrupt cops are corrupt cops.