UPDATE – Still searching for the original source of this insert card
Our best guess was that it could have come with the WOTC Team Rocket Themed Deck Box, as I had one as a child and the insert is Rocket themed.
I have since raided my childhood collection of related stuff and pulled out four VHS tapes and a VHS double set. I am now leaning more towards the idea that it could have been from the UK version of: Pokémon The First Movie
Will post some additional info and pictures about all these VHS tapes in case anyone has more suggestions or is mad enough to go hunting. But most likely the WOTC Deck Box or Pokémon The First Movie (UK VHS) is the best current guess.
These VHS tapes have not been opened since the early 2000s, anything I took out from the boxes as a kid is lost to my shoddy memory haha, the remaining stuff has been sat there for over two decades.
Up First: Pokémon The First Movie
The actual Mewtwo Promo 14 has been removed. I know this because it sits in my collection.
This is the remainder of what was inside:








Up next: Pokémon The Movie 2000
Well, I got quite emotional opening this one up, surprising me inside was the Pikachu 27 Promo card. Who knows why childhood me did not take this out of the case, and I have a couple of these in my childhood binder anyway. I do not own a single graded card, it has never been my thing, I’m a binder type of collector. But WOW, I am going to get this graded just for nostalgias sake, do not care what score it gets and it will be my only ever graded card. Unfortunately, it was just the tape and the card inside. The card was loose though, and I have now put into a top loader. Does anyone know if it came loose originally, or was it sealed in plastic? Perhaps younger me ripped it open then left in in the box.



Up next: Pokémon The Movie 3
Again, any card that was in here was taken out by me as a child and present me now holds in a binder. There is a leaflet though.





Finally, two that I think were unlikely to have had this insert, but worth posting just in case and for documentation purposes:
-Mewtwo Return The Movie + Free Tape
-Pikachu’s Winter Vacation







Well that’s pretty much my leads on where that insert came from exhausted. I have a LOT of Pokémon memorabilia stuff, but these seem the most logical source as they are linked to the TCG.
Hope somebody will eventually pull a copy from somewhere soon! Absolutely dying to know where it came from.