Congo Democratic Rep. Overprint Oddity

Scott 343 from the 1960 wild animals overprinted series:


This was found in a recently bought lot. I suspect the top stamp overprint is just a perfect smudge of the normal at bottom. This is a CTO stamp with full gum and the cancel is definitely on top of the overprint. There are also specks of ink to the left of the giraffe's neck which I believe to be setoff/transfer, probably of the "cancel" printing.

This is probably an interesting but not valuable freak, but I was wondering if it might be another type overprint that I should be trying to track down? And does anyone have something similar to show?

I only have 1 Opt on Sc#325
Do I recall "Floortrader" having a bevy of these Opts?

I have a screen grab during my research, called "anniv of the CCTA"
which shows numerous "varieties" of the Opt, errors and mistakes.

I do not have the link and do not want to offend copyright.

I have three stamps which appear to have similar CONGO overprints but these are on three of the woodcarving set from Katanga:

As an aside, just watched "The Siege of Jadotville" (Katanga)
from Netflix

64% -74% at rotten tomatoes