Well, hopefully that means something much more treatable. Or maybe something that will resolve itself. Nailing down a cause can be difficult, but I think it is a good thing you have eliminated two incurable diseases.
Keep on digging. I am sure you will find the cause with time. Most of us spent a lot of time just to get the crappy news that we have some form of IBD.
I am glad that you did not get that diagnosis. You may want them to check for Giardia if they have not already done so. But symptoms should go away after a few weeks if it was Giardia.
Let us know how it all turns out.
D Bergy