Recreate Similar Virtual Orchestral Tracks with Given Samples

Hello, I'm a classical-cross-over flutist and I need to release a few of my cover songs which means all the backing tracks need to be re-produced (aka. I cannot just use a karaoke track). These aren't complicated music, and I won't change the flute part so there's no pdf sheet music that needs to be created.

I'll provide all the mixed-down tracks, I just need help to re-create backing tracks in the tempo/timings/style/keys of the originals, with software instruments. I won't mind if you take some creativity with orchestration, that'll be great actually, I'm NOT asking for a 100% replica, as long as the lead flute part is not changed (because unfortunately, most of the music videos are filmed already, so I can't have the fingerings be different)

Please see the reference tracks on my YouTube. Again, just the flute part that I want to make sure stays exactly the same:

- Angels We Have Heard On High https://youtu.be/YZn-lU82TNc
- What Child is This https://youtu.be/nXkO9whh2Jc
- Amazing Grace https://youtu.be/G-Y0B4ZTIEQ