We are missing part of the story:
Somebody pulled the Ingram groups apart to separate the groups into individual bills - as much as possible - flattened those bills somehow, and tried to finger print a few of the bills. Who was that? That job would have taken time and effort! Normally, it is restoration people and archivists with special training who do such work ... in places like the Burke Museum in Seattle where Mr. Kaye works?
Those are the people with special training who usually get the first 'up close and personal' look at artifacts and form opinions about what the artifacts are saying (or not saying). Those people are usually 'in the loop' of higher level discussions which take place trying to decide the story an artifact is telling and how it relates to other facts 'in a case'. There can be documents which 'document' the discussion and decisions which took place, regarding artifacts.
That work would have been required in order to inventory the money and get a count, and as a preparatory step to finger printing any bills. Individual separated bills were then placed into evidence folders as per the Ckret video and photos. But who did the work? Neither Kaye or anyone else says anything about this part of the story. There would have to be a record of this at the FBI and perhaps some photos.
In Ckret's photo you can see the blackened bills that were finger printed vs those that weren't.