xml_date

sets the date format that is used to parse data from the data set

string xml_date;

The xml_date config is deprecated since v5.2. You need to use date_format instead like this:

scheduler.config.date_format = "%Y-%m-%d %H:%i";
...
scheduler.init('scheduler_here',new Date(2019,0,10),"week");
scheduler.load("/data/events");

%m/%d/%Y %H:%i