What is the voltage, at rest, 5 minutes of operation after you take it off an overnight charge? What is the voltage when you stall the hydraulics?
Fill the battery with water, and confirm (not just run the automagic filler, but look in each cell) charge battery 8 hours and allow to cool 8 hours.
What is the voltage at rest, and then what is the voltage when the hydraulics are stalled all the way up.
Your battery meter readings and lift cutout are common symptoms of a battery with a few dry cells, maybe from an automagic watering system that is stuck and not allowing water into some cells, (or 1 cell), or has some other battery problem.
the next test if these do not show anything would be taking a specific gravity reading on each cell with the battery pretty much fully charged.
Your battery may read a full charge, and then go down that quickly, if it was only getting a 1 hour charge. We call that a "surface charge", so you may want to confirm that the charger really is running 8 hours a night, and not getting shut down when the last person leaves in the evening.