Stray Dog Bite

Location: Alabama. I live out in the country where people dump dogs and there are packs of feral dogs. There is no animal control and no animal shelters in my county. There is a stray dog that sometimes shows up to rummage in trash cans for food. He hasn't been aggressive before to humans but does not like my male bulldog. I have already adopted 2 dumped dogs and all shelters in neighboring counties have said sorry, we are full. I tried posting pics before on adoption sites and Facebook to get someone to adopt him but nobody responded or someone would respond then ghost me. I didn't want to get charges for shooting a random dog and tbh the idea turned my stomach.

Cue today, I am at work and my son (M18) calls to tell me his gf (F19) was in the yard talking to Amazon delivery and this dog came and lunged at the delivery driver. The gf caught the dog and it bit her in the hand. My son captured the dog and put it in a crate in the yard. I've tried calling the nearest vet 30 minutes away and they told me to call health dept. I did and left a voice mail no answer yet. Knowing how slow this area is, I dont expect an answer by today. I called sheriff's office and they told me "Welcome to - County, we just say shoot the dog and see a doctor." My son's gf says she is fine and doesn't plan on doing anything she is trying to reassure my anxiety. Her mom wants the dog tested for rabies. The dog seems to be normal looking and is fine in the crate but I am worried.

I dont have homeowner's insurance because I literally just inherited the property from my dad. My sister and I inherited it and I moved from Florida to here and I am working on getting everything I need set up. My dad left no instructions on anything that needs to be done. What do I do next? Have the dogs tested for rabies? How liable am I for her injury since it's not my dog? Im sorry if I am rambling I an panicked and spiraling because I don't need this right now. I dont have a lot of money and this property is all I have to my name.