Mr. Gaider definitely said that it was false that the last two LIs were both race-gated. His tweet was not at all ambiguous, and I trust his grasp of grammar.
So, if Viv is indeed an LI, she will not be race-gated.
Though I do dread the possibility of her heterosexuality.
Bioware threw us a curve ball when they gave us Solas hetero elf only... Anything's possible at this point
I literally said the one thing Bioware won't do is make a heterosexual or homosexual LI race gated and they did it anyway.
At this point, the final LI could be a sandwich and won't be surprised. Won't. Be. Surprised. 
I've just realised that when one is revealed, the other one is also confirmed. So suddenly one thread will fill with joy and celebration while the other is filled with sadness and my Cersei drinking gifs.
Ikr let's hope we get something SOON, but not Bioware "soon"
that'll take months