Once you work your way through the game to the Playground Camp, this is where you will find the wombat.


When talking to the wombat, you can pick any dialog here at the camp, since he is easy to recruit!



"How about becoming scavenging friends?"



"You're the one who actually does the scavenging."



"20% of the loot."



"Let's go!"

Once the bulls show up at the bookstore, select:


"But let's play a game where we're not."



"on some rooftop with binoculars watching you."



"thinking about joining."



"an appliance store that has not been looted at all."



"But how about we give you a lead for some big loot!"



"We'll show you the big items store if you leave his loot."



"No, I really don't have any beef with you."



Wombat lost all items :(



"He's mentally disabled!"



"Of course we didn't. The bulls did!"



"You can find a way better group than us."



You should have the "Sorry, Wombat" achievement now!

NOTE: Don't do this achievement if you are also wanting to get the "Professional Scavenger Guides" achievement (Brought loot worth over 700 points to the guild), since the wombat will loose all of his items, and the bookstore has some of the highest value items.

Here is the text only, more concise dialog selections (the bolded selections are the most important to select exactly):

Location: Bookstore
Once the bulls show up at the bookstore, select:
"But let's play a game where we're not."
"on some rooftop with binoculars watching you."
"thinking about joining."
"an appliance store that has not been looted at all."
"But how about we give you a lead for some big loot!"
"We'll show you the big items store if you leave his loot."
"No, I really don't have any beef with you."
Wombat lost all items :(
"He's mentally disabled!"
"Of course we didn't. The bulls did!"
"You can find a way better group than us."

I hope this helps someone out!

NOTE2: I'm not sure if this will work, but once you see that you got this achievement, you might try exiting out of the game and coming back in, and see if it will restart the bookstore scene from the beginning, and give you a chance to go through it again and not get the wombat beat up so that you can keep your loot and not have to start all over from the beginning again! I only see the game save indicator in between going to a new location, so maybe this might work? Leave a comment if you try this and it works or not!