Sorry, happyheathen, only just checked back on this thread.
I would say report this to both the governors and the diocese.
If this school is anything like ours, the governing body will have an admissions committee, whose job it is to list the applicants for places in rank order according to the admissions criteria. And it's then this list that's send on to the LEA for them to use when offering out the places.
If any of the criteria are church attendance, then the admissions committee is RELYING on the vicar's reference to enable it to rank applicants. If the vicar's reference is not reliable, then it follows that the ranking list could be wrong and, therefore, that places are being offered to the wrong children first.
By the way, when we last reviewed our admissions criteria, we were told that the diocese (and by implication all C of E dioceses) were insisting that vicar's references should contain nothing more than information relating to the admissions criteria.
In other words, if the criteria were attendance at church at least twice a month for at least a year prior to application, then that is all that could be recorded. So, if Mrs X had attended that often but never given a penny to the church, her child would still meet the criteria. And if Mrs Y had not attended that often but had donated £6 million to the steeple-rebuilding fund, Mrs Y's child still wouldn't get in.
Looking at your school criteria, you have no right to appeal based on your church attendance, by your own admission. But you could argue that your child would have been higher up the ranking list (because there would have been fewer children meeting the criteria 1, 2 and 3 ahead of you) if the vicar's records of church attendance had been more accurate.
You'd have to provide evidence that his records weren't accurate, though...