A speech pathologist probably wouldn't treat you without an okay from an ENT. It is possible to provide therapy and make problems worse, so they would want the ENT to review and determine the cause of the hoarseness. Many times a speech pathologist will not make a diagnosis. Speech and language symptoms are often a sign of something else.
There might be a surgical option as well...When I discussed my thyroidectomy with my ENT surgeon and the possibility of losing my voice, he said he does a lot of vocal cord repair surgeries. I don't know any more than that, but might be something to look into as an option with a very skilled ENT surgeon.
You might try a good speech therapist or a voice/singing/speaking coach to strengthen your muscles...
There is a laryngeal nerve that can hit while doing surgery. This would cause a weak or hoarse voice due to the vocal folds receiving a lack of innervation. Sorry I don't know much about treatments, just pathologies at this point.