Stuck in quest "The Bigger Picture"

Im stuck in the quest "The Bigger Picture"
I have followed the trail and parcour of cheese to the cat "boss" room and got the "Razorouse King Tail".

I have tried dropping it in the carpet before the sign, but it wont work, and now i don't know how to leave the room, anybody any ideas?

 

EDIT: somebody else has the same problem as me currently, we're both stuck here.
And restarting and switching world all doesn't work either

 

i have the same problem i can't finish the quest i have tried using /kill and stuff but i still can't finish it

 

also stuck in the quest, if there is a hopper under the sign it ain't working

 

I have encountered the same problem

 

I found the same problem, and an honest solution would be to exit out of the rat place, and like use spells to fly across to the mushroom or skip the part.
I was on warrior and I was able to just fly across to the blue mushroom that I was supposed to go to.
Mods please don't ban me on forums.

 

The mushroom can also be reached from the top bed over the edge via movement spells. Until the issue is fixed thats what I would recommend. And it should probably be fixed by putting barriers in the way making that skip impossible