I'm not up to speed on that area of 4A law.
Is this really new ground? Or, just the application of existing government disregard for the 4th Amendment to a new set of facts?
I guess it will really boil down to whether a reliable informant supplying sufficient information rises to probable cause?
On the other hand, I think there is case law about getting a warrant when there is time and you don't have any excuses like evidence being destroyed or moved in the meantime. So, why didn't the cops get the warrant? A little concerned their informant wouldn't stand up to scrutiny? Was a real magistrate working that afternoon, and the cops figured he/she might refuse the warrant application?
Hmmmm. I wonder.