Can't find Yulete's Lab

In order to summon Angry Frankenroid in Magatia PQ, someone(not the party leader cos i heard it's glitched) needs to enter the door after the haste/tele portal stage and talk to Yulete before he runs off, leaving behind his summons

The party leader can go in, too. I've been in a pq where the leader went in. I believe you also need to give romeo/juliet the letter you find in the first stage in this room, before you move on.