Well, we're not talking about some member of the public/someone off the street but a Depository employee. Tricky business.
An employee of the TSBD is just a member of the public but even if they're not, the DPD don't have to fake a document to impress an employee of the TSBD. It doesn't make sense. However...
My working hypothesis is that there were two sets of curtain rods, one set found in the Depository, the other taken from the Paine garage. The latter set were tested on 11/25-----------
The original document (with release date 3/24) was not made public (and only came to light in the 1990s!)
IMO this was to merge the rods found at the Depository (which were marked with the digits 275 & 276) with the rods taken from the Paine garage (which--------in a blatant contrivance--------were 'marked' as Exhibits 275 & 276). Those numbers are a real giveaway.
Again, I believe we are dealing two different sets of rods.
...this does make sense, to a large extent, but there's still a lot of uncertainty:
Why do two curtain rods come in four pieces?
Is there any other evidence that the rods were found in the TSBD other than Fraziers' mystery caller?
How is Rankin's letter to Hoover tied into this?
Why the change of release date by Day?
At the very least you've demonstrated corruption in the processing of evidence but it would be satisfying to have an interpretation of the various documents that didn't leave so many tricky questions.
PS: What is the latest doc you posted?