While interesting for a conspiracy theroy, the element of unbelievability trancends the potential for disbelief.
And while the "greatest trick the devil ever pulled..." aligns itself with your theroy, MY understanding of American Liberties and it's ties to the financial ramifications of the newly formulated alliance under the Euro-Dollar, are not as complicated you are suggesting.
Besides, the sites reasoning is false, especially considering the Hebrew root of Melchizedek, is Moloch. See Paradise Lost for a secular interpretation of who he is, or trust me when I say he is a false diety.
For that reason alone I know that George Lucas and Steven Speilburg would not even consider addressing the coming of the anti-christ (or as the site suggests, the Messiah) as it pertains to archeology.
Indiana Jones is not researcher looking for the cause of the worlds troubles, nor is he the type to fix them. All he wants to do is steal artifacts that will bring him fortune and glory.