I hadn’t heard of that, is this speaking of eternal flame fixtures?
But as you have hinted, one dodge currently used by Caesar is to allow multiple faith monuments. I wouldn’t mind seeing a humongous menorah next to the Mt. Soledad cross if it came down to that.
On the same spot that is inacceptable as well. I have nothing against menorahs or moon crescents in their own spaces. National parks are not COEXIST bumper stickers.
Yes, an eternal flame on a grave is a clear symbol of satanism, objectively speaking.