So apparently this place got a lot of random glitches, after having done the dungeon the HARD way, doing at like 20 levels lower then one should be I finally had killed each extra boss to clear it and got teleported to the boss by using regroup with Ignis, but it was no boss there...
I managed later to actually face the boss and even get the sword, I read afterwards that a lot of people do not even get the sword doing the dungeon with no bug or glitch before coming to the boss.
Unfortunately I pulled my power cord while moving over to my PC,,,,,,,,because there is no way in hell I am redoing this dungeon again when this thing can happen + a lot of other bugs when its such a dam hard place to fight in. Gotta have to be super over leveled before one gets here if one has to redo it. Which is sad I really wanted to have this weapon before I met Inis, most people seems to have beaten the game lol before getting this sword as the last possible sacred sword, so would be really cool to have it before doing the level 10 story quest :)
Bah, might go back there but I will go Berserk if the dungeon glitches again.