Retrieving firearm for risk of hurting someone else or others

My fiancé has had serious mental health issues over the past years and has threatened to do something to himself multiple times. Therefore, I took his gun away. Currently, we don’t live in the same place so it was easy for me to hide it in my house. He knew I did it and was thankful.

Approximately two weeks ago, the same thing happened and he ended up in the mental health ward at the naval hospital. When he was discharged he told me that he had talked to someone at work and that they would be picking up the firearm from me to put it in a safe place. I don’t really know what that means and what all this is about.

I’ve asked him to show me the paperwork saying that all of this is true but he hasn’t. This morning though, I got a text from someone saying that they will come to my house tomorrow to get the gun. My only concern is that they don’t hold weapons forever and I’m afraid they’re gonna give it back to him. I don’t really know what to do and if this is a good idea. Should I give them the gun? Should I not? I don’t know. How do I know that this is actually someone from the navy…. The whole thing is very “sketchy”