CROKUS9 posted a comment to my THEORY #6535 and made an extremely good point:

"And to add to your theory.. It was a Mexican prostitute who wrote " he is mar" on the wall..If Jared Renfrew told her to write it, he would have said "ellis mars" and to a spanish speaking person, Ellis Mars sounds like "el es mars" which means "he is mars"

Also:  the Mexican prostitute must have written is as she was facing the tile and Renfrew was not in position to have written it.