Do not use the unit, it is faulty and could kill you. Keg King should send you a new unit and arrange for the faulty one to be sent back to them or destroyed.
Actually I think that I have seen someone on YouTube put a hop bag in a keg then rack down the hatch and then carefully removed the bag. It might have been gash slug or Craig from craigtube
I'm not sure if it is best practice but would lining the bottling bucket with a grain bag be worthwhile. The bag would probably need to be removed prior to racking but it should take all the hop matter with it.
Pluto guns can be tricky to use but when you get the knack they are pretty good.
What serving pressure are you using?
There's a possibility that your beer may be over carbonated
I have Casey's ESB in the fermentor right now. Started on Saturday @18° with old faithful uso5. Bought the temperature up to 21° today. Will keg her up early next week and put his Amarillo ale on. I have done that one before and it was amazing! Going to dry hop with a little extra Amarillo this...
They are a good airlock. Never had it blow apart like the two piece one did that one time bry-97 came to town. I don't use any of the old classic style airlocks I have. I find most of them are poorly manufactured because of the excessive flashing and the parting line shows that they can't even...
Recently did that one with 1kg ldme @ 18° 4 days and 21° 6 days with a danstar ale yeast. Dry hopped in the keg with a little simcoe. Come up pretty nice for a k&k :)