I believe it was your post #60 that mentioned the COLB being unsigned. You are technically right. However, on the back was a statement to the effect that the certificate was a copy of an original document or abstract. "Signed" Alvin T Onaka Ph.D the registrar.
That statement was made from a manufactured rubber stamp. This included a copy of the gentleman's signature. Cos' that is what it is, just a copy. A dozen people could have wielded that rubber stamp, not saying they did though.