Sir/Madam, on the phone you are a disembodied voice. I do not give any personal information out over the phone to anyone I do not know personally. If you are what you say you are please either contact me at an agreed future time or please show up with a warrant either for my arrest or for any specific property to be seaized. Needless to say I will cooperate with any warrant. As for any investigation you may or may not be conducting clearly my cooperation will be a function of you courtesy and politness and lack of intrusion into my personal affairs. In response to your if you've got nothing to hide comment. I respond "If you have some reasonable grounds for suspicion get a warrant."
Now the above said it seems there is at least one out of control FBIie maybe more. They could have surveyed state records in Maryland which I gather maintains more extensive records than many other states. Stay well - Stay safe - Stay armed - yorktown