Hello,
Sorry this has been such an ordeal. I spent some time trying to figure out what's going on, for some reason PayPal is returning a denied transaction when looking it up in their system, but I've found a workaround to fetch the completed one. It looks like a bug in their system has two separate transactions associated with the same ID in their database. I've patched our source code just for your particular purchase so it can correctly mark it as completed. Try checking your library, you should have access to the game again.
Thanks for you patience, and sorry about the delay getting it fixed.