he denied it AFTER they searched his house for the person. they can't just search your shit when looking for someone. the whole "we knocked and a door to your secret cache flew open" is the reason they used for the warrant (since technically they arent allowed to).

He probably realized this after giving them permission to search for the person, but at the point it's too late.

edit: the initial search and warrant was for a person. warrants are very specific about what you can and cannot search.hence why they needed ANOTHER one