There's 6 tools I am aware of that can be used for this type of repairs (corrupt data in JPEG image data). Apart from that I have seen a Russian lab showcase repaired JPEGs and a Pakistan lab I think in a FB video.
1 Jpgfix (hard to find so link:
https://overquantum.livejournal.com/9832.html), but I never took the time to figure out how to use it.
2 Jpeg Repair Shop.
3 JpegMedic (looks really, really nice!).
4 repair-jpeg (really hard to find so link:
https://directory.s2services.com/jpg-bmp.htm).
5 JPEG Recovery from hktech though in their latest update the editor disappeared.
6 And my own tool JPEG Repair Toolkit.
If you just need to repair damage due to a few bad sectors, which what this challenge is supposed to represent I think then Jpeg Repair Shop + something that offers content aware fill is all you need.
For the HDDGuru challenge I suppose only 3 tools will do:
https://youtu.be/ukf0hBjZjzA