The ants you witnessed taking the key suddenly come into the room. As do several other insects. But they don’t appear to be moving with purpose as when Qlat commands them – it appears that something the spine is doing is drawing them here.
Luckily, your test spell isn’t strong enough to cause any real damage when it detonates. Moments later, the ants leave – this seems to be Qlat’s order. The other insects linger, but just fly about aimlessly.
You take some time to think about this. You didn’t detonate when you entered – but you didn’t notice any insects besides the dead beetle. So perhaps the spine is attempting to cast a spell to lure insects and then attempt to destroy them. Your ether is controlled by your consciousness, though, so you were able to resist.
Making an object cast a spell automatically as soon as it has ether in it is something very difficult under normal circumstances, though. So difficult that it implies something about these spines which you weren’t aware of before.
The spines are an illusion, someone is manually casting the spells!
The wands themselves could be a kind of focus or calibration beacon. Maybe even a signal to let an observer know where a particular wizard (based on ethereal signature) is at a particular moment… Maybe you should hurry to get that key before an observing wizard decides to snatch it while you’re in this closet.