I bet a decent number of those voters just don't want to download multiple files for a single add-on
Which you still haven't fixed
I doubt you can even make a script inside Ground_ files.
1 : If I put a script inside Ground_None, it won't work, just setting the ground to an N.
2 : If I put the ground file inside a script add-on, that won't make it show up in the environment menu ground chooser.
Unless one of these two problems aren't problems and they actually work, that isn't possible, sorry.
Or if you mean make a .zip with both files in for the downloader to put both files into their add-ons.