I tried opening my right rear door on my 2016 RX350 the other morning and it would not unlock by touch, fob or inside unlock. The lock button simply would not pop up. All other doors worked fine. Two days later it worked perfectly.
Is it possible that a portion of the mechanism froze or ice formed on it... We did have some pretty cold weather... mid-20s? It occurred the day after I went th the car wash.

 

Most likely it froze when you went to the car wash. Monitor if it does it again.extended low temps tend to trigger locking-unlocking issues.

 

maybe the child lock got tripped?

 

Child locks prevent opening from the inside only.