That's not the same as being a copy of the original record. The Certification is the "short form", known more descriptively as the "abstract" version. It's called that because is an abstract of the latest information from the "original birth record".
Yes, it's evidence of the facts it contains, but it's not a copy of anything. It is a generated on request abstract. Generated either directly by looking at the "original birth record", aka "long form" aka "vault copy", or more likely these days, from a database which was populated by looking at the "original birth record." But of course what was posted was an image, not a document, and there is really no good way to be certain the image is an authentic representation of the original Certification document. It's more certain that document image appearing to be "photoshopped" actually was, than that one not appearing to be "photoshopped" was not.
But that was appears to have been edited. In any event it was altered, and even it were a paper document, it would be invalid.
Put another way, the Certification is a copy of some of the information on the "original birth record", but it is not a copy of the record itself. Such a copy would look almost identical to the original, which the Certification does not.
Whether it has been altered or forged is another story. The point is, demanding some other record because that kind of certificate isn't good enough, is false. It is good enough.