Your DA is probably elected; they don't have a boss other than the people that elect them. Again, Texas law is possibly different. They work independently yet together with law enforcement and the court system. Our DA would never be in a position to deal with a matter that was not of the most serious nature like murder, drugs, robbery and burglary, etc. There is probably a particular prosecutor that handles the less serious cases and you need to find out WHO that is and talk with them.
If you hit a brick wall everywhere, got to the clerk's office where these kinds of records are filed. It is the one place that may be able to get you to the exact right person. Clerks also interface with everybody from law enforcement to prosecution to court. They are a neutral entitiy and are there to help everybody (in theory).
Ask for the clerk, the one that is elected- could be called the District Clerk of Clerk of the Court. If she is not there ask for the clerk in charge of criminal matters. Introduce yourself and tell them that you don't know where else to go.
1) Tell them that you are trying to get a man prosecuted that has made terroristic threats and tresspassed on your property and that you are afraid of him and what he might do next.
2) Tell them that you have reported it to law enforcement and they didn't make a report. (They won't be surprised by this, by the way)
3) Tell them that the man came onto your property posing as being with the DA's office
'getting evidence'.
4) Tell them that the man is upset over your PETS and you think thats why no one is taking this seriously.
Then ask them who you should talk to to get this taken seriously. I'll bet they'll go out of their way to help you.
By the way, I'm a District Clerk....
Ask them