Real answer: In the movie, Kermit has a doppelganger who is a Russian supervillain named Constantine. Constantine escapes from the gulag at the start of the movie, finds Kermit and takes his place while letting Kermit get captured by the police, the police believing Kermit to be his evil doppelganger. That's how he ends up in the gulag.
Fun fact: That's where this meme template comes from. Muppets: Most Wanted is a great movie tbh, you should watch it. It has Ricky Gervais in it but it's really funny even in spite of that.
Real answer: In the movie, Kermit has a doppelganger who is a Russian supervillain named Constantine. Constantine escapes from the gulag at the start of the movie, finds Kermit and takes his place while letting Kermit get captured by the police, the police believing Kermit to be his evil doppelganger. That's how he ends up in the gulag.
Fun fact: That's where this meme template comes from. Muppets: Most Wanted is a great movie tbh, you should watch it. It has Ricky Gervais in it but it's really funny even in spite of that.