Your facts indicate you should consult a second attorney for an in depth interview with every single document you have as well as your complete written summary of the facts.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
The facts you have provided do not allow anyone to answer your question. Malpractice is a conclusion that is reached by comparing what the attorney did under the specific circumstances he or she was acting to a standard of care in the practice area and community of the attorney. That analysis requires someone to know all of the facts and circumstances facing that attorney at the time he or she made the decision to dismiss the case, and then to know what the standard of care was based on those facts and circumstances.
Keep in mind that if you could have simply re-file the case and the statute of limitations had not yet run on your claims, there is no possible pay you were damaged, and any claim of malpractice would evaporate away.
If you believe you have an attorney malpractice case, you should locate one or more attorney malpractice attorneys either here on this site (in the Find a Lawyer section) or elsewhere and consult with them, allowing them to learn all of the information.
Good luck to you.
This answer should not be construed to create any attorney-client relationship. Such a relationship can be formed only through the mutual execution of an attorney-client agreement. The answer given is based on the extremely limited facts provided and the proper course of action might change significantly with the introduction of other facts. All who read this answer should not rely on the answer to govern their conduct. Please seek the advice of competent counsel after disclosing all facts to that attorney. This answer is intended for California residents only. The answering party is only licensed to practice in the State of California.
If the attorney did not get your consent to dismiss the lawsuit, you should have another lawyer review your case. The statute of limitations for legal malpractice is one year.