That's a stretch though. People don't usually speak like genies in that what they're saying is only true in a literal sense. With all the flak IM2 caught for being so SHIELD-heavy, they may be deliberately trying to stay away from that.
So like I said. Where will the super woman come from? Cap 2? GotG? Both?
Sure, it seems unlikely that Szostak is Janet, though I don't believe I would mind her at all in the role. Just saying that the possibility doesn't really go against what Fiege said.
To your question about the super-powered female, my preference would be to establish Carol Danvers in the SHIELD TV show for 1 1/12 seasons and have her transformation to Ms. Marvel flow into Avengers 2. Other than that, I'm not sure what the other possibilities are. Janet probably won't be introduced until Ant-Man which is after A2 and I'm not sure who from GotG would fit. Perhaps Scarlet Witch could be introduced with a somewhat altered back story.