Retro Cave from Mystery Sphere Gamma does not return top evolved pokemon to the deck instead removes from game entirely

Unfortunately me and Mateo.Jaksic played a very long game that ended about 10 minutes ago,

Not sure if this is retrievable,

However he used Retro Cave from a Butterfree with Mystery Sphere Gamma attached to a benched Gengar, and I have 59 total cards, the Gengar was nowhere to be found, did not go to the bottom of the deck. I couldn’t post this bug report from the game because the game was long and ended up being more than 32000 characters.