I suppose she could get some benefit from molasses, but I think she needed fresh soil and some proper watering to get her going, but she is well into bloom and it is going to be hard to totally fix her at this point... just getting to harvest would be my goal.
Molasses is mainly for the soil microbes to feed on. It is sugar in the perfect form for them. For the plants there is a little magnesium and sulphur for the plant, and a bit of iron but not in the amounts that the plant really needs. Molasses has become a sort of bro-science thing in the cannabis world, and you will hear all sorts of stories about how it sweetens the buds and such, but if it were that easy, it would be common knowledge. It's hard to say anything bad about molasses, but I think its benefits are greatly overrated in anything but an organic water only grow. At any rate, don't overdo it, and I don't think you will hurt a thing by adding 1 tblspoon per gallon.