Ah, sadly that isn't going to be easy. It's likely in one of the SharedAsset files, commonly 0 or 1 as creators are pretty lazy.
However, these files aren't exactly easy to surgically extract things from. If you delete the entire file with the animation in, it could remove items unrelated to the animation and trigger a crash (or at least cause missing textures). It might also cause a crash if the file isn't present as the code will be unable to read it properly. Of course, the higher numbered sharedasset file could contain the animation too given it's a new addition. I'm not saying it's impossible, most of what I just said is kind of a theory given I'm no Unity coder, just that it might be difficult to extract the animation to bypass it.
But, again, it'll likely be the SharedAsset files found in the YourBoyfriend_Data folder. NOT the .RESS files, the .ASSET files (the extension is important). I'm no coder, but I hope you have success in finding a way to bypass the animation. ^^