Wrong Battery

Location: Georgia

My sister has a 2021 VW Taos. A month and half ago she was leaving work and her car wouldn’t start. She called roadside assistance and they jumped her car. Before she went home she called around to see who could install a new battery but didn’t find anyone that worked on VW until she had gotten home and they were about to close so she decided to go the next day.

The next day the battery was completely dead and the car wouldn’t start so she called roadside assistance again and found out that they do battery replacements as well. They dispatched a secondary company and that company charged her about $500. She was told $250 (in line with what a battery for that car would cost) was for the purchase of the battery and the rest was for the labor. She paid prior to the work being completed.

As they were there installing the battery my sister saw sparks flying from under her hood, the car alarm was sounding, and the windshield wipers were going. A few minutes later they told her they had completed the installation of the battery. She got into the vehicle and the car started but all of the warning lights were illuminated on the dash and her steering was locked. She got out and informed them of what she just experienced and they said they would double check it. About 30 minutes later she gets a call from the company that dispatched the roadside service asking how her experience was and that’s when she realized they had left. She tells they what happened and they said she needs to have her car towed to a shop to have a look at it.

She has the car towed and the mechanic at the shop says he will take a look at it the next day. The report from the mechanic is that roadside service installed a battery that was much too small for the car and it short circuited the vehicle. To fix it all would be over $1,000. My sister tells her insurance company what happened and they say that the roadside service company should be responsible. (Roadside is through the car insurance company) She had to beg for an itemized receipt from the roadside company and when she got it the battery line item showed a cost of $150. The second party dispatch company says they are not at fault for this issue and denied her claim. But would issue a “goodwill” check for $500. Her insurance company said to file a claim with the roadside company’s insurance. She gets that info and calls and they say there is no current policy. So basically the company is either uninsured or they have a different company. Should she sue her insurance company or all three parties (insurance company, dispatch company, and roadside company)?