My dog was bit at the dog park

We walked by the dog park 3 days ago and the other dog named Tiger with her owner were inside. Tiger were barking to my dog across the fence. I made a mistake and thought the barking were out of excitement and eagerness to play. My dog also wanted to go inside so I brought her in. Tiger stopped barking after that, but the meet and greet had a bit tension. They stood still side to side for 10 seconds and then they both walked away. My dog started sniffing around. I thought it was over and looked around a little bit. Suddenly they started fighting, as I approaching them, Tiger’s owner pulled my dog away (it happened right next to her). This happened about 1-2 minutes after we entered the dog park. Then she took her dog away and left while I was checking my dog. I didn’t see the wound and my dog appeared normal, so I also left. After getting home I saw this wound. I took her to the vet and she was taken care of. My dog is the friendliest dog you could have met, she’s never been aggressive to other creatures. I guess Tiger got nervous and suddenly bit her. There was no sign of warning from Tiger before the bite, no bark no growling, nothing. And my dog didn’t do anything, she just walked by.

I met the owner today and told her that my dog was bit that day. The owner didn’t say sorry or asked if my dog is okay. She first blamed me for bringing my dog in while seeing her dog were barking. She showed no willing to pay the vet bill and said her dog is not aggressive at all. For the very least I asked her to send me the medical record of Tiger. She took my email, asked for my dog’s name and even asked me where I live. I was so angry and I forgot to ask for the owner’s contact info. I only know the dog’s name. I haven’t received the medical record yet. What should I do?