Ahem.
The evidence against Led Zep is that, in rock and roll Heaven, lyrics count too, and rock and roll songs with lyrics that appear to have been penned by either a 15 year-old lovesick girl or a 16 year-old Dungeons & Dragons playing boy carry a lot less weight than "Meet the new boss, same as the old boss."
Also, as much as I love Kashmir, rock and roll Heaven does not recognize a suite of violins as having the same gravitas as a Fairlight or, in this case, a Lowery organ.
On personal note, I prefer The Ocean and the epic When the Levee Breaks (which was an old blues cover) along with Kashmir to the other LZ tunes you refer to.