Stuck in the Fighters Guild 3rd quest (The Prismatic Core)

Hello,

I'm doing the Fighters Guild questline with an alt (already did it with other characters before) and I ran into a bug in the 3rd quest, The Prismatic Core.

I do the first part (in the Ayleid ruin in the past), then go to the Earth Forge, help Merric at the forge, defend it against the mobs; then, Merric tells me we should flee and... he stays standing there. I'm supposed to go talk to Aelif with Merric following but he stays still next to the forge; I can't talk to him and I can't talk to Aelif.

I tried to tp away and come back, I've tried to quit and restart the game, the situation is still the same.

I've tried to abandon the quest and restart it, redo the Ayleid ruin and when I go to the Earth Forge I'm directly at the stage where I have to talk to Aelif with Merric, I don't restart at the beginning of that part where I have to help with the forge.

So, it looks like I'm completely stuck.

Is it a known bug? Has someone done the questline recently?