Technically, the Golan Heights isn't "northern Israel", but an occupied part of Syria. Only about 20% of the population (Druze) have taken out Israeli citizenship, despite the practical advantages of doing so.
There was no reason for Hezbollah (or their allies) to strike the area. If they fired the missile, they missed their intended target. It's also possible that the missile was a stray Israeli Iron Dome weapon. It's unlikely we will reliably know which was the case, since Israel obviously would blame Hezbollah regardless.