Uber Driver here:
There are a few variables here the OP does not address.
In LA there are options for “higher end” services like UberBlack, UberBlack SUV, etc with much higher fees. $19 for a relatively short ride would not surprise me there.
Was surge pricing in effect? On new years eve I made almost triple what I do on a typical saturday night, surge levels of 3x-4.7x were hitting solidly for several hours (ex: a ride normally costing $10 would be $30-$47) a $6-7 ride with a surge could easily be correct at $19)
I am not familiar with this area the ride took place, but was there significant traffic/time involved. Several large metro areas have adjusted the rates to less for mileage more for time due to drivers consistently finding themselves with 5 mile rides that take an hour to complete due to traffic.