Legal Question in Criminal Law in California

Yes, you can be violated even if the DA elects not to file a new case; in fact, prosecutors often do this because it's easier to prove a probation violation.

You don't get a jury trial on a probation violation, and the DA doesn't have to prove the violation beyond a reasonable doubt, just that it's more likely than not that you violated.

Since you already have three years in prison hanging over your head, the DA could decide it isn't worth the trouble to file a new misdemeanor that won't get you any additional time when it's easier and faster just to send you away for a violation.