She should have set her flowers by now, to be honest.... and now, she's not even able to fight for the 12 hours of light you're giving her... Personally, I'd remove her from the tent and let the others have more room... Perhaps you have a friend who has room in a veg tent she could share some space with? Perhaps if she got more light, more growth, she would indeed flip to flower when the lights are flipped.... just a thought...
Good luck!