Okay, that is a little weird.
The games against bots, I can see how you might think that it's anonce playing on Bonbi's account because the score is actually decent all of a sudden. But if you look at the last couple of games against actual players, pretty sure that her KDA is way too low for that to be anybody but herself (0-6-0 on Ahri, 2-12-8 on Vi...)
After the Ahri game posted above in which she ragequit, Bonbi played one game of Lulu by herself and then played 3 games against bots with Masamune, followed by another 7 games with Masa against humans.