The way you have couched your question is puzzling, as nobody, including you, could tell in advance what is feasible long-term without first attempting to solve the problem. Such problems as you describe are highly variable in their resolution, taking anything from a couple of weeks to years depending on many factors. I do not think posters on the internet, however well meaning, could possibly answer your question, and indeed, might proffer completely wrong advice.
Does it have to be a choice right now between being a concert pianist and not playing at all ? Would you not still want to enjoy playing the piano anyway, in whatever capacity you could ? I would be inclined to commence the process of careful relearning first, and not worry too much about whether anything is too late until your mechanism is again fluent.
Speaking from personal experience, and as a ferociously compulsive improviser, I would be very surprised if improvisation, however intense, were the cause. My problem was painless lack of control, so perhaps that is different, but I found improvisation a great help in correcting it.