Toyota Highlander 2012-- front passenger door stuck in locked position. Can't unlock with key fob, unlock switch on door or door handle on inside.

I am responding to my own post in order to update others who may have the same problem. As expected, the problem was a faulty door actuator. I ended up having the actuator repaired by an auto repair shop. They told me that door locks with this problem can "be sticky." In terms of the specific problem of the door being stuck in the locked (and closed) position (thereby hindering access to the faulty actuator), the repair shop tells me that to address the lock's "stickiness", it took brute force to get the door open (specifically, two big guys using brute force). Thankfully, they were able to get it un-stuck this way, rather than having to break open the door panel which likely would have resulted in some level of permanent damage to the door panel and potentially the dashboard.