Welcome to TBN.
How do you know the battery is OK? Have you done a load test on it? If not, what tells you it is not the problem?Verify good clean solid ground at the frame/chassis, for the negative cable. Also make sure the battery post cable connections are unable to be moved without a wrench- ie. snug- tight. How old is the battery? How many hours on the clock?
Did the symptoms appear suddenly or over time, and now causing a no start condition?
To those more familiar with this model, is there a main fuse, 60 amps or similar? PTO lockouts? Neutral safety switches?. Etc?
TIA,
CM