You have made a very common error. The first time you run
el = Explore Outliers(
it is pointing to the "dt" data table. However, by the time you go to run the second time, you have created a new data table "dtQuant", which is not the current data table as far as JMP knows. And of course, it will not find outliers. To fix this, all you need to do, is to force JMP to make sure it is pointing to the correct data table.
el = dt << Explore Outliers(
On another topic, using "j" as a variable name can sometimes run one into issues. JMP has a function called j. Even though you can have a variable called j, it can make reading the code confusing.
Jim