Yes that area in the Grand Canyon is off limits and contains mummified remains. The areas on the map also have Egyptian names. makes you wonder why it is in the US at all?
I've spent far too long studying Egypt - about 12 years. I knew I was getting some bits right when I started getting dream visits telling me basically to shut up about it by some priests. I think they were the protectors of knowledge. Some bits I can talk about. Some bits I can't. Basically I get ill when I get close. Ancient knowledge - yes, knowledge of the gods - no.
I have found that there were "Keepers of the Lights" - which were a priesthood that were followers of Osiris, and kept the relics of his a secret within the order. One of which were the everlasting tomb lights. These lights shone basically forever, but occasionally were broken releasing a liquid metal. The order kept the remains hoping for Osiris' return to repair them.
As an engineer I have worked out what they were and how they worked. That bit I can tell you about as it doesn't affect anything. It's just a very long story!
So...Egypt... I could talk all night and still not be finished.