New boot camp soft download

There's a way to do it, but it does require a Mac with macOS to be able to poke around in the Boot Camp Assistant app (Show Package Contents). There's a text file in there, keeps a list of the models and files to transfer for each. You would need to find your model (e.g. "MacBookAir8,1") and copy down the entire link next to it to fetch the right software. That is, assuming that a security protocol does not bar the way.

If that doesn't work, you back up the data and perform an Internet Recovery (Command-Option-R) to pick up macOS Catalina. That should give you Boot Camp 6. Once you are able to run the BCA, you go to the Utilities menu to fetch the software. You can then save it to the same stick that has your installer.

--Nate

Glad you got it solved. You may want to verify that you have the latest firmware updates. To do this in Windows, hit the command key and the letter R to open a run box. Then type. "msinfo32". Under the system information branch, you should see your model ID and what's called a "bios version." if I'm not mistaken, Catalina ended its run on about 2022, so if you're firmware isn't somewhere around there date wise, it would probably benefit you to install the latest build of Catalina anyway, and then destroy it.

--Nate