Get IR flood lights to light up the approaches and crop. That will give you much better video definition than just relying on the camera emitters.
Turn off the IR emitters on cameras within the grow, they will cause problems if they are within a few feet,.
3 thing rippers don't want is noise, lights and time, so keep an eye out for cleared paths, damaged lights.
Super thin grey thread strung thru the woods at upper chest height will give you an idea where and when they are scouting. Deer usually keep heads lower, don't snag it except on game trail and leave tracks.
Just run long lines perpendicular to the approaches. Once they walk into it, there no putting it back and hiding the passage.
Driveway motion sensors send a signal to the house ( 4 distinct chimes) are another option to look at.
Two things jump out...Did anyone else know you were cutting the next day?
How did the rippers know they were ready unless they snooped earlier?
Either way, they scouted the area prior, knew a route to the greenhouse at night and attacked on a full moon. Now you have their MO for the next grow because they are coming back.
Look at the calendar now, you know the next ripoff date within 72 hrs now. Oct 1 is Harvest Moon this year.