Probably some threads around, then people just kinda moved on. I think that if this was Atlantis, there would be abundant evidence of something ancient. All we gots is a foot. So as far as I would say it is still open - unless there was a mention of this in one of the podcasts and they said no. Other than the foot, I don't recall any references.
Sounds like you have you work cut out for you, Jules, develop this theory some more!