Bet:
High on something.
Gonna either get the kids or nobody gets them.
Gonna die trying (suicide by cop).
Takers?
Maybe, but it doesn't quite fit.
The full chain of events that I got was that he had put his kid in that school last week, and the Mom had court papers that allowed her to pick which school kid went to, so he hadn't lost custody, rather just the right to pick schools. When Mom showed up at middle school to get the kid, the school called the dad and asked him to come in and sort it out. So he was initially invited. Perhaps he knew it was going down, and loaded up, but it sounds to me like he just went to a meeting with school and ex, and *expletive deleted*it escalated.
As far as ZOMG MAGS AND AMMO!!! Dude had a valid CCW, his carry piece, and one spare mag on him, and one mag in the car. Also there were "some loose rounds of a different caliber" in his backpack. That's not loading up for trouble, that's having a normal EDC, and a backpack that was used for a range trip last week. If he wasn't an ANTIFA *expletive deleted*che, we'd be talking about media blowing up his "arsenal" and how that's a piddling amount of firepower.
Now, that said, he was definately an ANTIFA and anti-police activist, and that I'm sure colored his encounter, and drawing on two LEO's, one of which is grappling with you, is a great way to die. I'm just not sure this was a nascent mass shooting or suicide by cop vs. just a bad day and some bad choices.
ETA: Also, in case I wasn't clear, this has all the hallmarks of a justifiable shooting by the LEO's, despite what Oregon protesters are saying.
This video seems to have a good breakdown
https://youtu.be/r4tfM7yqCfU