I am sorry to hear about your unfortunate visit. The man you describe is Mike Castro, owner of Bowen Ranch. It sounds like when you pulled up, you inadvertently turned into his ‘private’ area, where he parks his personal cars (junkers too), behind the little house. This is what set him off. He does occasionally get a violent temper tantrum towards people, especially if they don’t follow his rules, some of which are not posted anywhere. Most of the times I've spoken to him or his other helpers at the pay area, they have all been nice to me.
For first time visitors, when arriving at the ranch, you should pull in front of the little house and stop at his stop sign, get out and fill out the little envelope from the bucket with the info on the sign, put in your $5 for a day visit, $10 for overnight per person.
Upon leaving, go straight - slightly left, follow this path to any of the parking areas on the property. There are two or three on the top of the hill with his home, but the main parking area is down the path (which can be rough on low cars). There is a large parking area that has some tables and camping sites around the outer edges. Be careful here not to park beyond his posted signs. In cases of emergencies the fire vehicles need access to areas down there so he posted no parking beyond this point signs. Camping is allowed at any of his tables or you can car camp in the main lot, but I don’t recommend that as too many people pull in and out turning up dirt on your campsite.
If you are completely turned off by his attitude now, when you reached the entrance to his ranch, there was a rough road on the right with brown signs… follow that rough road, making all left turns for 2.2 miles, you will reach a parking area called Freedom Trail which is on BLM/USFS lands. Camping is permitted here also, just no fires currently with the high fire hazard postings.
Again, it sounds like you were prepared to take care of our beautiful oasis, do visit again, and I hope you have a better experience.