Female posing as a Male, I think.
Transgender Teen Arrested for Montgomery County School-Shooting Plot
https://www.nationalreview.com/news/transgender-teen-arrested-for-montgomery-county-school-shooting-plot/
MoCo Press Release...
I don't believe the DC "letter" has anything to do with legally defining a "collector" under MD statute. It is subject to interpretation (not necessarily by MSP, could be the Courts).
"boner fide" that Biggfoot mentioned below...
Depends on the configuration, and possibly purchase date.
Check the copycat provisions below.
https://legis.delaware.gov/json/BillDetail/GenerateHtmlDocument?legislationId=109607&legislationTypeId=1&docTypeId=2&legislationName=HB450
This (FOPA) does not provide any protections driving from MD to DE if the firearm is a no go in DE. I believe that there needs to be at least 3 states in the trip for FOPA to apply.
If it were not legal in PA (and good in DE) and you took a circuitous route from MD thru PA to DE FOPA would...