Disney did make a video out of Pocahontas but they used her real life to create the movie. And because she was a real person with a real historical documentation, I’m not sure she can be incorporated into the Onceiverse. With Pocahontas, it would be very hard to explain how she was still alive in the 21st century if she doesn’t come from a mythological fairy tale land. Taking Pocahontas out of her historical era would take a lot of explanation. Also, I would hope that if they were going to have a Native American on the show (Pocahontas or Tiger Lily), they would hire an actual Native American.
I read the comparison of the lines but again I think it’s just call backs to one of the most acclaimed TV show of the past 20 years. LOST was, to quote my favorite review from TV guide when LOST finally ended, “lightning in a bottle.” Adam and Eddy have always been very proud to say they worked on LOST and how much they learned from it. We wouldn’t have Once without LOST so I think it’s very fitting and proper that they give callbacks to it. Also, I think it’s important to contexualize those lines. For example:
Snow says, “for as long as I can remember” which the post pointed is similar to a LOSTie saying “Richard’s has been here for as long as I can remember.” It’s important to put those lines in their proper context. With Snow, it’s the first day of the curse and that line is to show that she has no memories whatsoever of her previous life or what her life in SB is. With LOST, that line is to indicate that Richard’s story is a long and complex one (and one that kept fans frustrated and stupified up until his backstory was revealed).
So, in the end:
1) I really doubt Tamara is Pocahontas. I’m still holding on to the “daughter of Robin Hood and Maid Marian” theory but that’s looking less likely as well.
2) LOST references are all over OUaT
3) The lines may be similar but it’s important to contextualize them.