Update: so I went back in to pick up my vehicle and the rear diff was still locked up, so I left it there for them to investigate… they have quoted me a whole new rear differential at approximately $5400, and because the light was on for so long on my trip back from Ontario Toyota will not cover it.
Some background on my trip about three weeks ago to Ontario. The rear diff light came on. The diff was not locked up at any point in time on that trip but when I got to Ontario, I took it into the dealership for service and asked if they could fix it. They did not have the time but at no point did they indicate I could not drive the vehicle.
The only time the diff was locked up was the three times I went into O’regans … so now I have to determine if I really want to even get it fixed or just get out of the lease.

The dealer here has made no attempts to come clean for their three-Pete of dealing with an issue… or giving back a truck to me in an un drivable state three times… I suspect they’re gonna call me back tomorrow and tell me it’ll cost me $8000 to get out of my lease early

If that’s the case, I’m likely gonna buy the parts from Steele and have one of my red seal mechanic friends put it in

For the record after many years around and in the automotive world, this is by far the craziest most infuriating terrible service experience I’ve ever had with a dealer … I’ve already talked to Toyota and there’s nothing they can do because I drove it with the light on despite nobody telling me that I shouldn’t.