Unable to access Minecraft after Migration

A little over a year ago I migrated my Mojang account to my Microsoft account, this process was done successfully and without any issues that was until about a month ago. I had decided to play some Minecraft again after a break of a few months only to find I was unable to access my account, however a new account was present and no matter what I had done was unable to login to anything but the new account. From my understanding this new account is an Xbox account for some reason or other, the big issue is that it doesn't have Minecraft. While it was strange and alarming at the time I had attempted to do online fixes, which was probably a terrible idea. I would give a screenshot of the accounts in the launcher but I had removed the Original one from the launcher login while trying a fix. Obviously I have tried pretty much everything out there, including the suggestions by the Mojang team themselves via support. Now I had the game bought for me probably about a decade ago though perhaps a little sooner than that, it was done by a parent as I of course young at the time. So obviously no original receipts exist from a transaction done that long ago from another person I have contact with currently.

I am quite well unsure on how to resolve this problem, I shall soon take the time to look through an old device in hopes that it might the launcher installed but I am unsure of that. If anyone could point me to an actual fix to this problem or just point me to the proper support that would be greatly appreciated, the game means a lot to me since I grew up with it; and I would of course like to avoid repurchasing the game at all costs if possible.

Another note is that this is weirdly similar to other cases I've looked up but also not the same, so I am actually unsure if this is a duplicate of an existing problem or if it is a new issue that hasn't really been before.

Anyways here's some important that I do still have
- Installations
- Saves
- Mods
- A handful of screenshots taken when using the game
- All local files regarding the game and installations

:)