The second question is done too, with the assistance in Can't get Orekit to work in Matlab. What I improved in my code was to import some basic java file.
% From java
import java.lang.Math;
import java.lang.System;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.TimeZone;
import java.io.File;
Maybe it’s useful for others, thanks for your help.