I am able to blueprint a legendary Resource big mining drill and the blueprint works as expected (with the vanilla recipes removed).
If you take the blueprint that will not place, and attempt to place it on a resource patch, does it work?... If so, a vanilla mining drill has replaced the Resource mining drill before the blueprint was made. That blueprint can only be placed on resources.
That said, I would not advise enabling that startup setting. It was a suggestion from a user, but I have considered removing it or I need to make a significant change to the mod. Currently, Resource mining drill's next_upgrade is set to the original mining drill. When I first wrote the mod, I expected people to not trust the Resource drills and want to switch them for the original mining drill. Without the original drills for the upgrade, it breaks the use of the upgrade planner.