“Why do the Mooselimbs even want to build a Mooselimb Mosque next to the probably greatest temple in the world in Jerusalem???”
I can’t take credit for this line of thinking - it is something I’ve heard many times:
If you look at the scriptures with regard to Satan - you will see that everything he does is in competition with God, and is always a “me too”, imperfect copy. There are many examples, especially in Revelation (The Anti-Christ), and his followers share this trait.
That, in my opinion, is the answer to your question... When they were overrunning the Mediterranean centuries ago, they often built mosques where churches stood.