Ok so i killed all the mobs and the boss wont spawn in trial of sacrifice.

the above photo shows i killed enough mobs.

this 1 shows that i can still enter the trial after leaving even though all the mobs were killed (so i never got the boss)
i tried makeing everyone who was in the trial relog and enter again. im honestly at a loss for options here. Agaito offered to spawn me the boss (i couldnt find its name). That wouldn't truly solve my problem though anyway since i cant advance to the next trial. If anyone has any ideas on how to make this work besides wait for trials reset it would be awesome. Thanks in advance for any help.
update:
I stayed out of the trial for about an hour and it reset. So i can atleast do it again now

The boss's name is Astaria. Just did another trials run and it spawns for me this time
Also someone said that the boss is invisible and you have to walk around till you find it. I had characters spread out around the room so not so sure about this but i do admit i didn't try walking around much since i had toons on 4 sides of the room.