In case you like to know what happens:
I no longer heard chirping so I floated it again and no movement this time. So I proceded with an external pip. No visible movement in the shell and I couldn’t see the beak so I increased the size of the hole, being careful to stay in the air sac. Then I found the beak, which was malformed and it became obvious that the chick had passed. So I finished removing the shell and found that it only had the lower part of the beak and also appeared to be missing an eye. Attaching a few pictures. I also opened the other egg that was already deceased and it was malpositioned with its head between the legs.
I had someone “babysit” the incubator during the first week because I was out of town. Maybe something happened then that I’m not aware of.