@[Ariel] – you could work with the unique ID number of the paragraph style to identify it.
That is working beyond paragraph style groups.
var myDoc = app.documents[0];
var myID = myDoc.allParagraphStyles[3].id;
var myParaStyle = myDoc.paragraphStyles.itemByID(myID);
app.findTextPreferences.appliedParagraphStyle = myParaStyle;
Uwe