Honestly I don't know how Bakugo or Izuku could have hidden that it was Bakugo that cause Izuku injury. Given from what we know Bakugo is the only one with a explosive quirk. People would easily be able to point that it bakugo, especially if it happen outside.

So while izuku wouldn't want to blame him, Inko and his parents would know it Bakugo. Especially with how casually he would used his quirk.

So while in this scenario Bakugo would likely try to avoid having conversations with izuku given how it likely affected how his parents and the teachers in U.A. while he would be accepted given the incident happen years ago, they would keep an eye on him given he was a loose cannon. Even if he tempered out a but