Well it just happened to me this time on my 2018. Got in the 4Runner last night and noticed the Check Engine light and Track Off light were on, truck drove very sluggish but was drivable, figured I'll check it out in the morning. Well, this morning, much to my surprise there in the corner, just like you, a nice pile of leaves and sticks along with chewed up wiring. This all took place in less than 24 hours because I washed the car Tuesday afternoon, I clean under the hood, and Wednesday around 6pm the symptoms showed up. Put in a claim with the insurance company and now waiting to hear back from them. Did I mention that I hate squirrels!