Hi there,
I am very new to this forum and you made me do this reply because of your sentence:
The Geeetech GT2560 control board doesn’t have support to allow software control of the drivers
This is not quite right. You can add software support with a bit of soldering and marlin configuration.
Because I can not find any tutorial so I made one by myself and pushed it on Github.
Best regards from Germany,
Holzleim