From reading a few articles, it seems the clip was simply a spoof, and no full episode was ever intended to be made. I gather that it exists for two reasons:
- As a lighthearted jab at Fey, who (for the first time in eight years) had reprised her famous SNL role parodying Palin a week prior
- More importantly, as marketing for Palin's new book that we hear Dotcom complimenting here
On a similar note, here are all instances of a different actor portraying a young Liz: