2000 4Runner intermittent electrical issues.

This is my first time posting on a forum. I have several Gen 3 4Runners and really like them. I'm having intermittent electrical issues with the 2000 model. I found a post on this forum from 2021 by maddss99 describing a problem exactly like I'm having. There was no resolution to that problem though. It started with the drl's coming on intermittently and killing the battery. By the time I charged the battery, it was working just fine. Then intermittently when starting, the starter would stay engaged after the engine started. Shifting to reverse or neutral would stall the engine. Shifting to drive, the starter disengaged and the vehicle was driveable. The first time it happened the starter burned out before I figured out what was going on. I replaced the starter and the starter relay. It still happened intermittently but would go out of condition and work properly if I pulled the starter relay to test circuits. It's obviously the control circuit to the relay staying powered up, and shifting to drive removes the ground for the relay. I'm using schematics pulled from several places, including a wiring diagram manual which is believe is a reprint of a Toyota manual, specifically for 2000 4runner. I replaced the ignition switch, the problem still occurred. The starter control circuit is a direct input from the ECM, with 1 connector inline. It's clean, no corrosion. There is a circuit from the PNP switch spliced into this circuit, no indication what it's for, probably an input or feedback circuit. I replaced the PNP, didn't fix it. I pulled the underhood fuse block, all terminals inside are clean, no rust or corrosion. I'm starting to think ECM, but would like some input from someone who may have seen something like this before. The truck is bone-stock, nothing added, 214k miles. I've had it a few years, it rarely gets driven. Sorry to be so long-winded, but this has been going on for over a year, and I'm just not sure what to do next. Thanks for any help anybody can give me.