Sorry to hear your news.
If the panel asked about preferences and other appeals, I think they would need to be able to justify what relevance this had to your grounds for appeal for this school.
If the panel had access to supporting documentation, including details of the school allocated to your child - and this documentation was not made available to you - it does not on the face of it sound acceptable. It should be a fundamental principle that all parties receive the same
The fact that the decision letter refers to something you did not say is also a matter for concern. I think one would have to concede that the error is not critical to your case, but it hardly inspires confidence in the process.
The ombudsman or YPLA may or may not regard these points as so serious as to cause an injustice, but I do think it would be worth seeing what their view is.
Please note that if this is an academy, you will have to complain to the YPLA not to the ombudsman:http://www.elevenplusexams.co.uk/appeals/ombudsman#d6
With regard to the clerk's notes, if you have already requested them under the Data Protection Act, I suggest you write again, saying "Thank you for your response regarding the clerk's notes. The relevant paragraph is 2.42 of the Appeals Code (not the Admissions Code), and I trust you are proceeding with legal advice, as I fully accept you are entitled to do. You will be aware of the timescale within which you are required to respond to a request under the Data Protection Act, unless it can be shown that a lawful exemption applies.