I work with college students. I almost quit and gave up.
Since Botox is working for me, I've been able to continue in the classroom and at my second job in retail sales. I tell the students at the beginning of the year what my situation is. I find the students are my greatest supporters. (My customers too for that matter.) I just got the Spokesman Voice Amp from Soundbytes. I used it for the first time this week; I wish I would have found this device sooner. It definatly helps in the classroom! The students thought it was way cool. To answer another of your Q-my Botox voice is clear, steady but low volume, monotone and breathy in the beginning. Yes, SD changes how you talk and what you can say. I talk much slower. I talk less. With Botox, your life becomes cyclic. Periods of good, great, fair, can't hardly talk, and back around. It changed how I teach (for the better I'd say).
My advice to you is give Botox another chance and definatly get the amplifier for the classroom. Let your students and co-workers know what your situation is-I've not had anyone that was unsupportive over my two years of ADSD. Their encouragement helps especially on your "fair" days. Good luck to you.