Never heard of using Botox, but whatever works.
Had gastroparesis for a long time, but it was pretty benign, then had fundoplication and it went into complete paralysis for a while. I found out the hard way that oatmeal is not good for me. Lots of diarrhea.
Gastroenterologist put me on Cholestyramine and that has made all the difference. Slowly adding some fiber back into my diet.
I think I've been lucky to have good doctors.