Duval Betrayed His Father

It seemed to me that Duval at some point realized that having his father around was more downsides than upsides, and that is why Duval gave his Dad up as to the regeneration, and then told the FBI that Pritchard was dead.

Duval tells Dad "You have to stay away from my family" and in many ways that is Duval becoming a bastard like his Dad. Duval wanted to be the top dog in the family, and he resented getting upstaged by his Dad (who he had always resented).

Duval also probably realized that the great arrests thanks to Looking Glass were over, and having Pritchard around just as a drinking buddy was not worth all the danger that follows Pritchard around.

So Duval kicked his Dad to the curb, and now Duval is top dog at home, and he got to know his Dad better (and buried him again).