Iirc she was featured and was switched to main. Her label probably paid for it.
You remember incorrectly, lol. She's always been co-lead, they get 50/50 points towards the Artist 100 (in which she's currently the only one charting) and is credited separately in the Spotify page, not as a "(feat. Camila Cabello)" in the name. Same thing with IKWYDLS.
Camila is the lead as much as MGK, if Anything Camila sings and wrote the most part
Not to mention almost all media reporting it as Camila's song, but whatever, people will always still find a way to discredit the girl. MGK was barely unknown before this, no offense to MGK but she never has this success before.
Her chorus is the best part 
