Both vis and potestas mean power. The former is a masculine word and thus takes verus as the appropriate adjective form; the latter is a feminine word and thus takes vera as the appropriate adjective form. There is, in other words, no difference at all between vis verus and potestas vera. I quite like the alliteration of the two letters v in my version, though.
Infra means below/under rather that within, I'd say, but in any case, my word ingenium means an innate quality, which is surely what you mean. Power, in the sense you mean, is not actually coming from anywhere. It's not on the move, is it? It's just there.
Venit does, of course, mean comes.
However, far be it from me to argue with a PhD in Latin!! If nothing else, his/her version merely strengthens my earlier advice to take very carefully anyone's translation here on AnswerBank.