That's quite a tour you have planned.
My thinking on your bike choice is along the lines of what xilios said. Given you're concerns, I'd see if the bike shop will take the Kona back and refund your money. It might help to ensure them that you'll try finding the right bike for the tour through their shop. That said, I wouldn't get my hopes up too much. Most bike shops probably wouldn't take the bike back. You might be able to sell it for close to what you paid.
Now, people have toured the world on all kinds of bikes that were "less than ideal". You could change the gearing, order a set of expedition worthy wheels from Peter White Cycles, pull a BOB Trailer and that would put you in pretty good shape. If I did the same thing with my cyclocross bike I'd feel I could go just about anywhere with it. That said, on the trip you're planning, I'd almost certainly take one of my other bikes because I prefer using panniers.
Another place to look at touring journals is
The Trento Bike Pages and of course the
FLT Gallery is where to go to see over 200 examples of how others have gone about expedition loads.
Good luck getting the bike sorted and have a great time on your tour.