Restore MyNxt wallet from backup

Several years ago I was very interested in the NXT/ARDR/IGNIS project. Life in 2017 wasn't very kind to me on a very personal level, and I stepped away from the world of crypto entirely to focus on real life issues. 4 or 5 years have passed, and I have stumbled upon my old NXT and ARDR stash that was stored using the old MyNxt installation on an old hard drive.
I have a backup saved on my pc, as well as a couple of photos I took of my private key.
Unfortunately, the private key I took a photo of is NOT my wallet, and it is an empty wallet.
I am hoping that I was a little more intelligent with backing up my wallet file.
I have a couple of backup files which are .json file type.
How can I go about extracting my backup and seeing if it actually is the backup of my wallet?
This is a real grasp at straws here, but I used an email address to register back then, which I can prove via a photo of the contents of my wallet ( my email address is visible in the dashboard which is the same email address I used to register here ).
I understand that if I have not backed up the right wallet, that I probably don't have any chance of recovering my wallet, but there is no harm in asking.
Its literally been a number of years, and I am aware of how careless I was, but I hope there is a chance I can recover these assets.

Thanks a lot in advance for any help that anyone is willing to give, I really appreciate it.

My address is ARDOR-AB6F-N7HZ-PEJY-HUFL9

I have a wallet.json file or something similar, but I have no idea how to use it with the current setup.
If opened with a text editor it is a very long string of characters.

Hi Panda,

Thank you for contacting us.
MyNXT wallet was a 3rd party application that is no longer supported and the announcement was made long ago to allow users migrate their funds to the new platform before it was shutdown. This isnt something we can assist you with. However, you can contact vanbreuk on Nxtforum or an email to vanbreuk@gmail.com for more assistance.

Best regards,

Jelurida Support Team

Thanks a lot for your reply, I will reach out to Vanbreuk now.

Hopefully they aren't lost forever! :fearful:

I appreciate you taking the time to reply.