Legal Question in Criminal Law in Washington

It is unlikely that the police forged the warrant. Such a forgery would be easy to prove. In fact, it would almost inevitably come to light when and if the evidence is introduced in court, or even sooner. A forged warrant would seriously undermine the prosecution, especially if the evidence obtained via the forged warrant was central to the case. And the consequences for any police officer who did such a thing would be severe.

The law does not require a separate warrant for a safe. If the safe is within the area that the warrant allows the officers to search and if it could contain the evidence they are searching for (a home safe could not contain a stolen car, for example but it could contain drugs), then they can open it while executing the warrant. They may force it open if they can't readily open it without force.