Not sure why you have that, surprised if it even compiles. Remove the switch statement since it doesn't make any sense at all to have it.
I'd also recommend removing the "Ä" and "ä" since I wouldn't think that would be too compiler friendly because they aren't normal characters (pointing it out just incase).
You don't need SummonList for your summoned minion AI. You also need to call "events.Reset()" in "Reset()" in your minion AI so when they reset their events reset.
problem: My summoned npc does not conjure up their magic. I don't know why the do I have it just as written as above for the boss
Does your spellId exist? Make your sure GM is turned off because npcs will not attack you and you have "if (!UpdateVictim()) return;" which means if they don't have a target it will return and it won't run any code below it. DoCast has a 3rd parameter "triggered" for instant casting, it sometimes matters depending on the spell.
What do you mean by "go back away?" Do you mean corpse despawn?
question: what must you write so the summoned enemies at the dead go back away from the Summoner