.. Evidence room gremlin

Take a knockout gas grenade from the self. That ought to take it out.

Oh, yeah. You need some protective gear.

Like, a helmet so that you won't breathe the gas in.

There's a helmet trophy in McKing's office. That could work.

There's a hose at the holding cells. Take the hose and combine it with the helmet.

Put it on, when you are in evidence room. Now you can throw the gas grenade on the gremlin. Pick up the evidence gremlin.