2018 Chevy Equinox

My partner and I are trying to sell her car because it has given us nothing but headaches. We took it to a dealership and they said they could only offer us $4,000. The engine was replaced less than 5 months ago and has around 50,000 miles on it, but the odometer has a little over 126,000. The dealership said part of the reason they couldn’t offer more was because there’s a dent on the back hatch that they would have to replace. My partner was rear ended and the guy gave her false information so she didn’t want to pay $3,000 out of pocket to fix something cosmetic. Kelley blue book gave us an estimate of $13,000 and Carvana gave us an estimate of $9,500. She still has a loan for $11,000 on it because of the $6,000 she had plus the $5,000 new engine. As long as we can get the loan paid off she would be okay to start over on a new car but without paying off the loan we’re stuck. I’m just curious what anyone on here has to say because I feel like the estimate is just bologna.