I didn't get to having botox until after many years of hell, suffering badly and made worse by a lot of physios etc who mainly wanted to do high velocity manipulation to dislocate my joints. I didn't generally get exercises from physios at all, just high velocity manipulation or airy fairy massage which did nothing. Hence I now physio myself successfully. The idea with botox is to use the window of opportunity it gives to strengthen the muscles which are being inhibited by the tight muscles which never switch off to give the antagonists a chance. Ideally you would be supported by a good physio who could help activate the right stabilising muscles while they are not being inhibited and make sure it is working. You would want to make the most of this opportunity and good physio if you were so lucky. If not, quickly study shoulder anatomy and stabilisers yourself. Then when the botox wears off, you should not be back at square one but at square two or three! Good luck.
Joint group leader for South Central (Bucks, Oxon, Herts)