Don't Americans have the right for their lawyer or a trusted witness to be present during search warrants? If they do, why would police ever expect to enter without delay?
In a situation like this there may be a pause until the owner or lawyer arrives, but during that pause the people would not be permitted to be in the to-be-searched location without police supervision; the owner has the right to supervise police while they are searching, but they don't have any privacy right to do stuff there before letting the police in; if the lawyer's presence is required then whoever is in that location would let the police in and wait for the lawyer together with the police officers with neither doing anything until the search commences. If noone is present, then the police may seal the door while they wait for the owner or their representative to arrive; or, alternatively (e.g. if the owner is on the run), there is a process to recruit neutral witnesses from the community, e.g. having your neighbours supervise the search and sign off on what was taken out during the search.