It looks like there are more recent sales for this on SCM than through TF2Outpost.

http://steamcommunity.com/market/listings/440/Haunted%20Creature%E2%80%99s%20Grin

With the recent purchase prices around 1.4 keys in value or more, I'm not sure 1.2 is appropriate just yet. But, SCM often doesn't agree with trade values, so it might not be completely related.

Also, it looks like your ad has an offer of 1.3 keys on it. ( http://www.tf2outpost.com/trade/23671310 )

They hadn't traded the Grin, even after making their statement of 1 key 2 refined, so I think they still might be waiting for better offers.