What other theories are people who profess the "teach both sides" method of teaching evolution looking at?

They aren't looking at anything real. They oversimplify matters considerably in the Fine (?) tradition of Pascal's Wager that sees only "Either/Or" (An essay by Soren Kierkegard) between belief and disbelief of uninformed fundie Christianity. They see only a distorted dream world with no basis in reality. They ignore all other creation myths besides their pet one in "Genesis", e.g. Marduk the Babylonian creator, Brahma the Hindu creator, Isanagi and Isanami the Japanese creators, Pan Ku the Chinese creator, etc. "Both sides" is a gross oversimplification that lumps all other ideas into one opposed to fundamentalist Protestant Christianity. I am a Catholic, and the Pope accepted evolution years ago, as must all people who are literate in science. Fundies say Catholics aren't Christians. I'm reminded of a joke about a non-fundie who saw a building with no windows or doors in Heaven. He asked an angel what it was. The angel told him the fundies were in there. They believe they are the only ones in Heaven, so they don't see anyone else. My version of this joke is that the fundies' building is in Hell. I guess that's the truth, not a joke, though.