“What qualifications or who meets the acceptability to certify copies?”
ICH GCP Ref: 1.63
I think to answer this question you need to first consider what the process for certification will be.
For example, if the certification is of a document that is generated from a system, through a non-validated process how would a person go about confirming the data on the copy has the same information, include the data, the context, content and structure as the original data in the system? This may be more straightforward with some systems than others, is all information visible on a screen, or is some information hidden, does all data in the system print out on the report, if not is the data relevant, does this system hold an audit trail, is this available for the data being exported/copied? This may require someone with a different skill set than say someone making a scan or photo copy of a paper document where the process is much more straight forward as it is a direction comparison, and they may need to also assess legibility, before certifying.
Either way, the process needs to be defined and the organization must train those individuals who will be responsible of the process.