Photos are not required, the CEO's notes are the primary evidence.
You parked in a bay which at the time was restricted to BB holders or those engaged in loading for the sole purpose, according to you, of delivering several bags to nearby premises and thereby entitled to be parked. But you did not include this in your reps which appears odd.
You've now asked 'Is there anyway I can contest..'
But you have already submitted formal reps and are awaiting a response. Apparently the authority requested 'further evidence' which itself seems odd because you've not mentioned this and what could they require as further evidence as regards such limited reps.
In any event, IMO there's little to be done until you receive their response. If it's a rejection, then you would have to decide whether to go to the adjudicator or not, there is nothing more that you could do with the council.