You guys think like rocket scientists. Think very simple about it.
Why couldnt the three ammo boxes just be levers to unlock the forge?
We see the three swords of the families(bow, hammerhead, sniper) and subclasses ON the swords.
I recommend that one player equips a bow on arkus subclass, the next one an hammerhead with solar and the last one the sniper with void subclass.
If you extend the directions of the outter swords they're crossing.
So bow player uses right ammobox, sniper left one, hammerhead middle. If that doesnt work switch the sniper and bow player up.
(Megathreads suck)