Resolves yes if there is essentially a consensus among physicists that string theory is correct, and no if there is essentially a consensus that string theory is incorrect. Otherwise, resolve as N/A.
There is a (unresolved) conjecture called the "String Lamppost Principle" that says that quantum field theories incorporating general-relativistic gravity have to be string-theoretic in some way. (See for example https://indico.cern.ch/event/929434/contributions/3913286/attachments/2066410/3467937/Vafa.pdf.) I think this is a pretty strong indicator that whatever physicists do find will be string-theoretic in some way (unless they happen to overthrow quantum field theory and/or general relativity first, which seems unlikely).
Would Newtonian gravity count as "correct" for purposes of this question: a good approximation which nevertheless fails badly in extreme cases?
@metachirality What would count as yes then, that there exists a string theory which correctly predicts everything at all scales?