I think it's too early to make judgments. There really is not enough information here yet. I cannot see Sasuke ignoring his own child if he knew he had one after what he went through without his family. Everything he did was to make sure that such a horrific thing would not happen to another family and so someone like Itachi would not have to make such a horrible choice. I can't see him staying away so long if he knew he had a child. I think he still would have done his redemption tour but would have come back periodically to check on his family had he known.
As for Sakura fainting they might be combining the anime and the manga. She passes out more often in the manga, but it's usually from chakra exhaustion. She doesn't have as large a supply as everyone thinks. She has great chakra control, but not as large of a pool as some of the other characters. Whether or not she's Sarada's mom, we will have to wait and see. She looks more similar to Karin and it is strange that Karin's picture was behind the other one instead of in another frame.
Whether she is Sarada's mom or not, Sakura would have felt she needed to do this without bothering Sasuke because she knew how important making up for his actions was to him. She also would have wanted to show him she could take care of things on her own without relying on Naruto and Sasuke like she did when she was younger. I think that would be the main reason she didn't have someone find him to tell him he has a child.