"Diadema" appears to be a created name from the Latin (via Greek) work "diadem", just as you had surmised.
"Lodusky" is related to the following, 19th century, once-popular but now obsolete (in the U.S.A.) feminine names: "Ladusky", "Ludusky", "Laduska", "Loduska", "Luduska".
All of these names are variations of the more familiar "
Louise ", derived from the Germanic/Swedish/Slavic forms: "Ludovika", "Ludwiga", "Ludoisia", etc.
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Nanaea