I just traded for Octodad: Dadliest catch giving 4 keys and 3 refined metal on this trade:
http://dispenser.tf/trade/85330/
I did an offline trade after adding my keys and metal to a bot, and upon trying to 'exchange' it to my steam account, I got an error saying "Unable to offer item". I tried several times and continued having this problem.

I do see the item in my inventory, I just haven't been able to trade it to my steam account. I would appreciate getting a different copy of the game, but if that's not possible I would be ok with being reimbursed with the keys/metal again... Thanks!

I removed and re-added the item, please try again and report problem if there is any.