Could be temperature related, set them in the fridge or freezer for 5-10 minutes it should be no problem. If not, it could be whatever you used to clean with. Just let them dry for a bit and try again. Usually works for me anyhow!
I understand that, but whether it's stuck inside or out, the freezer will expand briar and contract the tennon. If anything I doesn't hurt to try :puffpipe:
The graphite pencil method works well in most cases but sometimes you need to sand the tennon down a little to make it fit correct. Be careful if you have to force the tennon in as when the pipe expands during smoking it can lead to a cracked mortise.
How much of it did you use? Seeing as it's being used to just really clean and maybe leave a little flavour for about 2 seconds after you first light it, the fact that it's "high test Moonshine" really isn't all that impressive. A word to the wise I wouldn't use it again.