Besides both being birds, what makes Dr. Spanko Jacques similar? Well, they both talk. Dr. Spanko speaks in "Anglish", which is a highly confusing language tangentically similar to English. A current project the Foundation is working on is a translator that would take Anglish and convert it to English. While the foundation has AI capability, their Text to Speech conventions haven't been strictly updated; there's not a lot of need. My theory is that Dr. Spanko either accidentally swallowed a translator, or he had one installed in the near future. It's been shown that Jaques can time travel, and Dr. Spanko has had many adventures before his capture by the Foundation, and I believe he'll have many more after he escapes one day.

How did he go from being a Corn Crake to a Parrot? It's simple: Dr. Spanko is an Eldritch entity, a cartoon character in fact. This was leaked by the author in a forum thread I believe. When he met Cinnamon, Jon's other bird, he was instantly in love, but not compatible, so to speak. What's form to an eldritch entity though? In a deleted segment of his Special Containment Procedures, Dr. Spanko meets SCP-682, who asks: "I asked for Dr. Spanko, and you fetid [DATA EXPUNGED] heaps brought me a turkey?", indicating this is not the first form Spanko has taken. Taking the form of a parrot, he courted Cinnamon. Also Jon says they try to bone all the time. Would it not make sense that an actor of such regards as Dr. Spanko would return to the show business in some capacity?

Additionally, Arin, Dan, and Jon are canon in the SCP Universe. Jon is INTERVIEWED by the foundation concerning SCP-3006, and Dan and Arin are Anomalous Items (it's a long list, do control F Arin).

Thoughts? Came up with this myself, thought it was interesting.

Edit:

From the author. Apparently no one can see past "oh no racism" to enjoy a story for a second, jeez.