John Carter flopped because of pathetic (but huge) marketing, absence of star actors, generally unknown story, tremendous budget, live-action inexperienced director and Mars. Disney wanted Avatar-level success from Avatar-like film. Anyway, it was pretty decent film on my opinion, especially in IMAX.
Here, in Russia, this film is fond of public, for sure.
But I don't see any connection between this and possible Uncharted movie. And Uncharted movie won't cost Sony/Columbia $250 000 000+ to make.