"A Study in Time" Quest seems to only trigger/advance when the party leader interacts with quest objectives

I play a lot of Coop with my girlfriend, and usually she’s party leader, but I interact with most quest stuff (because I’m a bit more impatient haha).

Twice now during campaign, we got stuck at this sidequest for a bit.
When you inspect the door inside the College in Imperial Era Welryn, the Skeleton Guard doesn’t let you through, until you present an imperial officer’s crest.

This is supposed to be a trigger for a Time Rift to appear, that leads to the ruined Era.
This Trigger seems to only work when the party leader interacts - which I think is inconsistent with how the rest of the game deals objectives.
Usually we never get stuck and I can interact with all sorts of stuff, even as non party leader, to advance quests.

I’d appreciate someone taking a look, and making sure this is consistent in terms of quest design.

Thanks EHG!

Actually, this might be even more complicated - I recently played the campaign in coop again with a friend, and got stuck AGAIN here for a bit.

Here’s what happened:

He was the party leader, I wasn’t. I entered the college in the Imperial Era and defeated the Monsters in the front room. He joined the Area then. I tried speaking with the door (the one where the skeleton wants you to show an Imperial Crest) and the quest did not advance - he tried talking to the door too and the quest did also not advance. We had to reload the Area and let him defeat some monsters in order to properly trigger the quest advancement.

I think this means, that the quest trigger right before the one that makes the Time Rift appear is weird. Does it trigger on Area load? Or on killing some front room skeletons?

Something here manages to make the quest go haywire if the Party Leader isn’t in the area.