UCB- stuff happens in life. Kids get mono, break an arm, miss two weeks of classes. If you are looking for an assurance that your kid couldn’t, wouldn’t, get barred or dropped- that doesn’t exist. But I’d say all things being equal, a kid who is highly motivated (you claim it’s the kid’s first choice of major with no parental pressure) and solid academic prep in that area, should be ok. OR- not ok, and have to either transfer schools or pick another major.
No guarantees in life.