My problem isn't with the safe itself, but the lock. I've got a lot of experience with pin tumblers, but none whatsoever with lever locks.
Here is the safe/drop box:

Here is the best shot I can get showing the levers:

Now, After finding the same model of box online, I've determined these are what the keys look like (I don't see any special warding or curtain interaction on these)

So, I've spent the last day studying lever locks and the mechanisms. I've had a cursory play with moving the levers which is fine, so I'm comfortable with the manipulation of those. My problem at the moment is where to apply tension to retract the bolts? Every lever lock I've seen examples of, has a curtain that connects to the bolts and you can slide this to move them or to put tension on them. This lock however I can't figure it out. The keys don't indicate any special nub that would engage this, the red and silver walls you see are fixed and static, they certainly don't move. Also, the keys that come with this model are double sided, however inspection of the lock only has levers on one side, so I think the other side may be a decoy?
My question to you is, firstly has anyone experienced this box before? Secondly, where should I expect the mechanism to move the bolts to be? I'm crafting a tension tool (a stick with stiff wire perpendicular) but I can't for the life of me figure out where to apply the tension.
I appreciate any time you've spent reading the above. Hopefully I can get this open soon!