Skipping straight to botox is a very good option for you. You have already tried dilators with no luck, so you for sure need more help.
If you have fear of penetration, doing PT might not be helpful, as you might not be able to allow the practitioner to do the exercises.
Often PT after the Botox procedure is even more beneficial, as you will have already done dilation, and the muscles of the vagina are more relaxed and more easy to manipulate with the botox.
I think Botox is a great option for you, give us a call and we can discuss it further.