when you 'sign' your name you are *certifying* something... sometimes it's as simple as 'you are that person'. At other times, you are certifying that certain information is correct... ie.. your address, your ownership of an item, or that you are a resident of a state, etc...
When an appraiser 'certifies' his appraisal by signing it, he is stating (certifying) that he believes the contents of the report are true and correct to the extent he has stated it. Apparently Jerry M believed that car to be correct when he did that report (from reading the report on KM's site). A judging report on the other hand, simply states what is visible to the eye, and doesn't get so much into 'belief' or subjective knowledge. It simply reports what the codes say, the colors, if they are correct or not, and then perhaps a subjective judgement as to condition, correctness, etc. In this case there seems to be some confusion whether this is a 'judging report' (per specific restored Camaro guidelines), or an 'authentic Z28 Certification'.
I have appraised vehicles for 'out of town / out of state' purchasers previously. I tried to make my report as factual as I could re reading colors, codes, conditions, etc much as Jerry's report does, but I also provided 'My subjective beliefs' where I believed something to be 'faked'. I suspect if Jerry had been writing the subject report for a 'prospective buyer' he would have been less reserved in his judgement and statements made in the report. When I read the report, it *read* more like a detailed 'Judge sheet' than a Certification of authenticity...?