Incarnation of Dread stuck on "bring blue rose"

I collect both the red and blue rose, go to Incarnation of Dread and still the fight does not progress.
Is this a bug or am I misunderstanding the mechanic?
(probably the former because the first red rose worked after touching Incarnation of Dread)
https://www.youtube.com/watch?v=HX8WOgIk0kE

The problem seems to be happening when I die.
If I dont die, I can progress to the next phase.

+1
played through phase 1 normally, 2nd invul phase won't let me "bring the rose" to the boss; nothing happens.

Neither the blue nor the red rose do anything when walking them to the boss. Infinite invul. phase :-(

Same thing here

I've been here for 15 mins already. Nothing happening.

i just lost my patience i walked around the boss for 10 min and nothing happened..lol this is insanely stupid design or bug.

Yep same for me. Lost ma fragment and could never be completed

+1
Happened to me too for my first encounter

Should be fixed now in patch 3.26.0c

Still happened to me right now. Died in the last transition phase, roses do not work after portaling back. Non-quest version. After a good 3-4 minutes it did transition, so at least there seems to be a failsafe built in.

Yep still bugged for me right now.
EDIT : as above poster mentioned i waited 3-4min in the arena dodging things and it unstucked