If this is a blood case, this delay is not unusual. The defendant will not be indicted until the blood labs come back. Officers can but usually do not issue a citation for the underlying traffic offense when they make a DWI arrest. If he didn't have a parole hold, his attorney MIGHT be able to get his bond reduced or get him a pr bond because the indictment was taking so long. However, because he does have the parole hold, there's nothing he can do but wait.
Macy Jaggers's answer to a legal question on Avvo does not establish an attorney-client relationship. Ms. Jaggers offers everyone a free consultation to discuss their case. Feel free to call her office at 214-365-9800 to make an appointment (phones are answered 24 hours) or visit her website at www.macyjaggers.com for more information about her services and recent victories.
If he has a parole (blue) warrant, he is not getting out. It is not surprising in any county that the blood test is not back; it takes several months some times. Given that it is a felony DWI (being the 3rd), he is not likely to get any sympathy from parole.
He should have a lawyer representing him and answering his questions at this point. That lawyer should be in control and have more information than any of us on this site can offer.