Trying to Report neighbors for Animal Abuse

I’ve been trying to anonymously (for fear or retaliation) report my neighbors in Houston for animal abuse for the last 2 months and the authorities aren’t doing anything about it!

I noticed that my neighbors (who I’m not close to) had 4 beautiful pit bulls that they used to let roam free in their backyard, but over time noticed that the dogs started to look sickly. I started hearing the dogs screaming at all hours throughout the night and stopped seeing them outside as often. A couple of weeks past, and they let the pits back into the yard more often, but there were only 3 of them, and they all looked really skinny like they were being starved. I mustered up the courage to approach my neighbor to see if she needed any help with dog care/walking (she is a very erratic and aggressive woman and has had 2 convicted felons in and out of the home in the last 3 years and has a lot of squatters in the home), and was threatened at gun point. I decided to put in a claim with the Houston SPCA back in March and still haven’t heard back from them/seen anyone come to visit the house! Even worse, I think they have started using the dogs for illegal fighting because the 3 babies looked so beat up and bruised when I do catch them outside and the yelling and screaming only gets worse at night. One of the dogs looked injured in its leg and I just want someone to rescue and help them before it’s too late and another one dies. What can I do?