Is there any timer lock on HKC jail's key drop?

I cleared the whole hkc twice, didn't see any key drop from corpse.

The key drops from "An Undead Warden". He has many spawn points in HKC and if he isn't killed he de-pops and moves to another spawn point. Pretty sure he is trackable. If not, one spawn point for sure is down in the Pickclaw area where Bigz would normally be, right in the middle of the grate. He doesn't add a detriment so it's OK to pull him along with a group of mobs.

Other places I've seen him is on the 1st floor in the back room (by the ghost named, I forget his name). On the 2nd floor right around the corner as you leave the room with the trap door to the North. In the Pickclaw area in the room next to where Brog is (in the bar area, above the leg on the floor that gives the quest).

I know this probably isn't what devs want to hear but it was so much easier to leave someone camped in the jail area and tinker to them as needed. The jail door doesn't stay open long enough and chasing the warden around the zone so many times was a giant pain in the rear to get the Bloody Shank.

Edit: Oh, I have also seen him in the room with all the undead dogs, hanging out by the door to the Handler's room. And in the library on the far end of the globe.

The undead warden doesn't have a long respawn timer (maybe 20-30 minutes?). We do what we can of the quest while we have the key. Then when the door locks (and if no one is camped inside the jail), we run back up to the dining room and go into the right doorway into the room where the dogs are. He usually spawns in the balcony right above the dogs (to the left of the doorway you came through from the dining hall), and floats along the ceiling across the stairs to the other side of the dogs' room. Just look up

Ok, thanks guys, I was thinking it can drop from any mob. I got the key, thanks again.

Actually, the key has dropped from another "skeleton-type" or "ghost-type" trash mob (probably a very rare chance), but I don't recall the exact name. I've also heard the same thing from another group of players on our server.

I have never seen it drop off of anything other than the warden.

Also you should note that the key is a body drop - not a chest drop. So if you're in the habit of not looting bodies, you may have killed the warden several times over and missed the key.