I think they should finally throw the book at the guy. He should have his parole revoked and go to jail. He should serve the 10 years in prison for violating parole on the original crime, and then he and his mother should be charged with every crime that can stick for fleeing to Mexico.
But then, I think he should have gone to jail for the original crime, rather than getting probation. The whole "oh, gee, I'm too rich to take responsibility" defense didn't set well with most people in Tarrant County, where I live, and where the original traffic fatalities took place.