Logically, if aliens landed and claimed they made up all of our religions, the religious leaders of the world would be the first to rise up and essentially say, "Bull-crap to that!" Then there'd be all sorts of backlash saying the aliens were heathens or demons or some other such thing, the truth of it all wouldn't matter, for in the grand scheme of things, organized religion seeks to get rich off of and exert power/control over those whom worship with them.
Now I'm not going to go on a religion-bashing rant, there are good people in the faiths of the world who do good things to help other people, but you can't deny there's been a lot of evil things done in the name of one faith or another through the years....As for me, I personally don't care what faith you are, nor your race, creed, or color, if you do me nor anybody nor anything else no dirt, you are welcome to sit down with me for a pint and some fellowship as a human being.
Just my two cents...