The writers made a distinction on Twitter about Alexandra and Henry, but not sure if the way they worded it ruled out Greg and /or Tamara surviving or being killed by it–they simply were not part of the scope of that answer. So I think it is quite possible for either thing to have have happened. All we know is that Tamara has said she is human, that she didn’t consider herself to be part of “your kind” when talking to Hook about the impact of the fail safe (or didn’t want Greg or Hook to know otherwise, if she knew she had magical roots). Hard to say as I think it is something the writers didn’t think about too deeply–so I don’t think Tamara will be RH’s child. Whatever her back story is, I think it will be more like Greg’s, if we indeed ever get it. She’s someone who ran into magic in “the real world” and hates it.
I also think the writers did not think about the fact that Emma has been in SB for an entire year, with time moving forward. I suppose it has been only a month since the memory curse broke, so maybe no babies were conceived and born in Storybrooke because of the curse. The writers didn’t TELL us that though. The only baby we knew about was Alexandra, but in retrospect seems odd that there were not any others.
“If I had a world of my own, everything would be nonsense. Nothing would be what it is, because everything would be what it isn't. And contrary wise, what is, it wouldn't be. And what it wouldn't be, it would. You see?” -- Lewis Carroll, Alice's Adventures in Wonderland & Through the Looking-Glass