This clearly was rational basis in a dressed up form. CA4 simply ignored all the real-world experience of the shall-issue states in favor of the speculation of MD and it's politically appointed LEOs. I'd guess that with all the conflicting stats from the pro and anti carry sides at the very least you have a wash and under true intermediate scrutiny the court should favor the individual right over the state.
CA4 and CA2 both were wishy washy about the inside/outside the home, it seems they didn't want to make a definitive call on it. Hopefully SCOTUS takes that as an open invitation.