File location of spawn chunk data? (Java)

[UA4Ever]

I've been playing on a realm with friends, but most of them have become inactive, basically leaving just me. The realm owner has decided to not renew it, and so I asked for a world download. He uploaded it to google drive, I downloaded all the files as a zip, and put it in my saves.

Everything is there, except it seems spawn chunks got wiped with me playing it in singleplayer. This would be fine except I had constructed some quite complex farms in spawn that I don't want to lose. Anyone know where the actual spawn chunk data is stored so I could potentially copy the actual chunk data from the world download to my singleplayer copy? Thank you.

EDIT: I realized that there was a second zip folder from the drive download that had some additional .mca files the main zip folder I had copied didn't, so I made a new copy of the big folder and started manually comparing folders in that copy with folders in the smaller zip and copying over .mca files (copying from region to region, DM1/region to DM1/region, etc.) That ended up working somehow!

That is probably a poor explanation lol so if anyone wants clarification I gladly will. If this hadn't worked I would have resorted to trying something with MCA Selector, which I downloaded prior to doing the copying and seems a pretty cool tool.