Confused
This is not something that your JC+ advisor should be having any say over, if you have presented a Fit Note then it should have been accepted and your attendance at the JC+ suspended.
I'm afraid you need to be forceful about this, contact the JC+ advisor and tell them that either they accept the Fit Note of you will have to escalate the problem, I appreciate that this may be difficult for you, but every time you attend you undermine the Fit Note as being valid.
As to the Decision being made on the 22nd, it's possible but there are no guarantees of it having.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems